Sen. Paul Laxalt (R-Nev.) expressed concern here today that too much money may have been cut from federal social programs when control over them was shifted to the states as part of President Reagan's economic program.

He said governors, including many Republican governors, had told him that "They've got a big load dumped on them here by way of new programs and we're not giving them adequate money. That is a problem."

"It may well be the case in a lot of these states--and only time will tell -- that we're giving them too much authority, too much responsibility and not enough funding," said Laxalt, a close friend of Reagan and the chairman of the president's task force on federalism.

In remarks to reporters after speaking to the annual meeting of the National League of Cities here, Laxalt said the White House and Congress may have to make some adjustments in the budget or that states may have to be granted new sources of funding if it turns out that these are serious problems.

There was little doubt on that score among the 2,000 mayors and other city officials from small towns and big cities gathered here for the league's 81st annual meeting. Many are already engaged in the awkward balancing act of raising taxes and reducing services in order to cope with less. The league's president, William Hudnut, Republican mayor of Indianapolis, called them experiments in "creative frugality."

They await anxiously the growing recession and the administration's proposals for more budget cuts early next year.

In his greetings to league delegates, Democratic Mayor Coleman Young of Detroit, where the official unemployment rate is already up to 14 percent and unofficial estimates of joblessness range to double that, said ruefully, "Let me welcome you to the great city of Detroit and say to you that as you come to Detroit you see the future of America. Unfortunately you might be witnessing future shock."

The mood among delegates has been somber with few expressions of unqualified praise for the president's economic recovery program and little of the fiery rhetoric opposing it that has marked similar gatherings of mayors in the past.

The only matter provoking strong definite feelings was the consensus of both Democrats and Republicans here that the league had been snubbed by the Reagan administration. Vice-President Bush and five members of the Cabinet declined invitations to attend, citing scheduling conflicts. The only Cabinet official who is scheduled to speak is William Brock, U.S. trade representative.

Reagan did send a message that was dated Nov. 20 in which he said that the budgetary changes and government restructuring are "not painless." He added, "I am convinced that if we all tighten our belts and carry the load together, we can turn the economy around and make our government work more effectively for all citizens."