What was going on when I was born?

BUYERS in the market for mortgage financing are being beckoned with tantalizing offers of quick loan approvals. Instead of having to wait a month or more, they are told, they can get an oral or written commitment within days or even hours. But while such an offer could be tempting to anyone who needs to sell or get into a home in a hurry, lawyers are warning borrowers to be cautious. The applicant may have to provide a larger-than-usual down payment, pay an additional premium and provide far more detailed documentation about employment, income and outstanding debts than for conventionally timed financing.

President Reagan will leave Tuesday for an economic summit conference in Bonn to press six other industrial democracies to adopt the policies that made the United States economy the world's fastest growing for the last two years. The 10-day trip, with stops in Spain, Portugal, France and other parts of West Germany, has been overshadowed by outrage over the President's plan to visit a cemetery that has graves of Waffen SS soldiers. Today officials said the White House chief of staff, Donald T. Regan, was seeking to shift attention from the cemetery visit on Friday to a previously announced trip to the Bergen-Belsen concentration camp site earlier that day. [Page 16.] Fears of a Recession But the President's trip is also clouded by new apprehensions that the American economy, which pulled other countries from a prolonged global recession, is showing signs of pushing them into another.

DESPITE his pledge of abstinence, Jay Kennedy sneaks out to the garage sometimes to catch the sports scores on a portable television set. But his two daughters, Corrie and Devin, check up on him, feeling the set to see if it is warm. It is ''the reverse of the parent-child trick,'' said Mr. Kennedy with a laugh. The children, he said, ''really don't miss it much. I guess it's been harder on me.''

Wherever he was today, George Steinbrenner must not have been smiling. On national television, the Yankees let a game slip away twice, which is not the kind of thing that is likely to keep their principal owner content. The Chicago White Sox, who seemed on the brink of losing in regulation and again in the 11th inning, strung together five hits in the bottom of the 11th, the last coming on a bloop single by Carlton Fisk that beat the Yankees, 5-4, at Comiskey Park. Yogi Berra, the Yankee manager, called his team ''snake-bit'' afterward, certainly an accurate description in light of today's proceedings. Steinbrenner, who was expected to attend the game, was a no-show, perhaps because of the weather: 44 degrees, windy and rainy.

TO enter the cooperative housing market in New York is to enter a world of shadows. It is a murky place in which buyers and sellers alike must often rely on the flimsiest of rumors and suspected trends to find their way. Turbulent submarkets, like investor demand for occupied apartments in converted buildings, further cloud the waters. The problem, according to brokers, buyers and sellers, is partly a lack of hard information about co-op apartment sales and partly the fact that what information does exist mostly concerns a narrow band at the high-priced end of the market, a segment that may not be reflective of what is really happening overall. Also, some experts believe that because the few published co-op indexes - notably the Corcoran and Douglas Elliman reports, both of which track recent co-op sales, though in different ways - are so heavily weighted toward the upper end of the co-op market that they may distort the perceptions of buyers, sellers and government regulators about the market as a whole. Many buyers and sellers are now saying, in fact, that much of the co-op market has softened - quite the contrary of the upbeat conclusions of both of the most recent of those two reports.

''SEAPORT'' is more than a word - it is a service mark, according to officials of Mystic Seaport, and they want the service mark all to themselves. Mystic, the southeastern Connecticut tourist attraction that is the largest maritime museum in the country, has a service mark on the word ''seaport'' in connection with museum services. Mystic officials say a waterfront development in Bridgeport looks like a maritime museum to them, and they are pressing the owners for a name change. The owners, the Williams family, have refused, and Mystic Seaport officials are considering their next move.

A fire at a psychiatric hospital here killed 79 people and injured 247 Friday night, and today Government officials questioned two representatives of the institution, the police said. The fire at the St. Emilienne Neuro-Psychiatric Institute began at 9 P.M. and quickly engulfed the modern six-story building in smoke and flames, witnesses said. The police said 410 patients were registered at the hospital. Officials said they did not know how many staff members were on duty.

A HISTORY OF ARCHITECTURE Settings and Rituals. By Spiro Kostof. Original drawings by Richard Tobias. 788 pp. New York: Oxford University Press. $45. COCA-COLA, legend has it, went from a marginal soda-fountain operation to its phenomenal success when the company followed a stranger's advice - ''bottle it.'' Spiro Kostof is a professor of architectural history at the University of California, Berkeley, who is known for the drama and intellectual excitement of his teaching, and what he has done in his ''History of Architecture'' is bottle what he has been dispensing in his courses. The result is a magnificent guided tour through mankind's architecture from prehistoric caves to the extension of Harvard University's Fogg Museum, which is only now being finished. The feel of the book is comparable to that of such panoramic television series as David Attenborough's ''Living Planet'' or earlier ones by Jacob Bronowski on science and Kenneth Clark on art. Indeed, in case no one has thought of it already, I offer free of charge the suggestion that Mr. Kostof and his book have the makings of a spectacular of this kind.

By last count, the City Department of Housing and Preservation owned 65 percent of the brownstones in Harlem. Next month, 150 of them, acquired by the agency because of tax delinquencies, will be sold through sealed bidding.

LESS than six months after his landslide, Ronald Reagan seems, quite suddenly, politically vulnerable. His decision to proceed with the visit to a German military cemetery next Sunday despite the rage of Jewish and veterans' groups and bipartisan opposition in Congress was a ''disaster,'' several senior White House officials acknowledged. Other setbacks, uncharacteristic of the Reagan Presidency, seemed to overlap: the rebuke that the House of Representatives handed out in rejecting aid for the rebels in Nicaragua, the uncertainty that dominated the end-of-the-week Senate debate on the President's compromise budget proposal, the resistance in Congress to a possible tax overhaul. ''Some of the shine is off,'' said Senator Charles E. Grassley, an Iowa Republican who describes himself as ''a loyal Reaganite.'' ''People are just a little less willing to follow the President now than four years ago.''

Western music is in an excavation period, a time when hunting for old manuscripts occupies the energy of a surprising number of talented artists and musicologists as well as legions of dust-sifting scholastics. The recent exhumation of 33 lost chorale preludes of Bach stirred the imagination of many people, aside from the musical importance of the find, simply because the idea of buried treasure fascinates us all. It appeals to the hunting instinct in the human animal. We avidly follow the detective work that results in the discovery of mislaid pages by Debussy or Verdi, of Strauss's last song or of an entire opera by Donizetti (by my New York Times colleague Will Crutchfield). And we speculate about what wonders may yet lie undetected in libraries and opera house basements. No musicologist has yet come upon the fabled 100 lost cantatas of Bach, which would rank with Heinrich Schliemann's coup in unearthing the four layers of Troy, but in this age of computerized scholarship who knows what is possible. At any rate, serious fans of treasure hunting, fed from youth on Robert Louis Stevenson and Poe, feel free to daydream. The lost Bach cantatas are the Atlantis of musicology.

Among those buried in the German cemetery that President Reagan plans to visit are soldiers from the Waffen SS division that committed one of the worst massacres of World War II, according to information from a German war-graves group and from historical sources. Although those buried in the Bitburg cemetery probably did not take part in the massacre, which occurred in June 1944 in the French village of Oradour-sur-Glane, the involvement of the division appears to have escaped the attention of West German and American officials who have been doing research on the graveyard since protests broke out in the United States. The announcement on April 11 that Mr. Reagan would lay a wreath at the cemetery next weekend brought an outcry from Jewish organizations, veterans' groups and others because of the presence of 49 Waffen SS soldiers among the dead. [Robert B. Sims, a White House deputy press secretary, declined to comment on the new information about the division responsible for the massacre. He said there was no change in the President's plans to visit the cemetery.] According to several accounts from Americans involved in the planning of Mr. Reagan's visit, Chancellor Helmut Kohl and his aides have assured the United States Embassy that there is nothing about the cemetery that could embarrass Mr. Reagan.