What was going on when I was born?

President Reagan's speech today began as what the White House described as an attempt to define a constructive bipartisan relationsip with Congress on foreign policy. But it has set off one of the sharpest confrontations between the Reagan White House and Congress. Administration officials said the wrangling may therefore make it harder than ever for Mr. Reagan and Congress to achieve cooperation in this election year on such issues as the Middle East, Central America and relations with the Soviet Union. White House aides said they had no hope or expectation of softening the criticism on foreign policy aimed at Mr. Reagan from the Democratic Presidential candidates.

The Federal Reserve Board, in its first overt move to tighten credit during the current economic recovery, today raised by half a percentage point, to 9 percent, the interest rate that it charges on loans to financial institutions. The White House said President Reagan was disappointed by the action and expressed the hope that ''this will not result in a further increase in the prime interest rate'' charged by banks. Within the White House and the Treasury Department, officials have expressed the fear that higher interest rates will choke off economic expansion and harm Mr. Reagan's chances for re- election. The Federal Reserve issued a brief statement saying it was raising its key rate, called the discount rate, simply to follow other interest rates upward. It said it was not aggressively seeking to drive up interest rates to head off a possible resurgence of inflation.

Britain told the Reagan Administration earlier this week that it disapproved of the mining of Nicaragua's harbors as interference with international shipping and asked American help in halting the mining, a British Embassy spokesman said today. ''We have made clear that we disapprove of any threat to the principle of freedom of navigation,'' said Andrew Burns, the press counselor of the British Embassy. ''What we have done is register our concern and said we don't like all this and tried to enlist American cooperation in stopping any recurrence,'' Mr. Burns added. But he said Britain had no plans to join France, which has not only voiced concern but said it might help the Nicaraguan Government remove the mines from its harbors.

President Reagan criticized Congress today for what he said was its reluctance to support the use of military force to advance foreign policy goals. In a speech here, Mr. Reagan said that Congressional second-guessing on the use of force had already undermined American diplomatic efforts in Lebanon and Congressional wavering had encouraged ''enemies of democracy'' in Central America. The President's remarks were the latest in an intensifying series of Administration complaints that Congress bears considerable responsibility for recent foreign policy problems. The criticisms, aimed at Congress in general and Congressional Democrats in particular, began after the withdrawal of the marines from Lebanon last month. Then, on Tuesday, Secretary of State George P. Shultz called for closer foreign policy collaboration between Congress and the Administration, and on Wednesday Mr. Reagan said Congress ''must take a responsibility'' for American setbacks in Lebanon.

Flooding from two days of record rainfall in the metropolitan area forced thousands of people from their homes yesterday and closed large stretches of major roadways. In Wayne, in northern New Jersey, police boats rescued people marooned in flooded homes at the confluence of the Pompton and Passaic Rivers, which were swelled by the rainfall. In Westchester County, the business district of the Village of Ardsley was closed because of standing water, and sections of major roadways were impassable. ''It's a disaster,'' said Governor Kean, who flew in a helicopter over the areas affected by the more than four inches of rain that fell Wednesday and Thursday.

Unemployment in New York State last month fell to its lowest rate in four years, the Bureau of Labor Satistics reported yesterday. Samuel M. Ehrenhalt, the bureau's regional commissioner, said the drop in unemployment was largely attributable to strength in the construction, wholesale-retail, service and financial industries. He said that an increase in New Jersey's unemployment figures by half a percentage point over February was not significant or a cause for alarm. He characterized it as well within the pattern of the last six months. Speaking at a news conference in his office here, he said the state's showing was a ''continuation of a strong situation.''