You'd think that standing wedged with 5,000 others would be enough for one evening. But no. An inaugural ball, like any high school prom, must have an after-party to carry it far into the drizzly night. A few hairdos got wet.

Among the most sought-after after-parties was one given during yesterday's early hours by Jane and Guilford Dudley of Nashville. Very fancy guest list (Claire Boothe Luce, John Connally, a baron and a barones, etc.). Dudley himself is an insurance magnate and a former ambassador to Denmark who has made scads of money and famous friends. In fact, a large percentage of the 100 guests who came to the midnight supper at the Jockey Club were indeed famous, and if not, at least acceptably rich.

Famous: Jimmy Stewart. "So Reagan's going to do all right?" somebody asked.

"You bet your --- he's going to do all right," he replied.

Rich: Mercedes Kellogg, New York socialite. "Didn't you love being on the list?" she asked one guest.

Famous: William F. Buckley, editor of the National Review. Ronald Reagan reads it cover to cover.

"Have you had an audience with the president?" one guest asked.

"Audience?" replied Buckley, who earlier had been deep into conversation with Henry Kissinger. "I don't like that word. I only have audiences with the pope. I have chats with lesser people."

"Well, have you had a chat with Reagan, then?"

"No," Buckley replied.

Famous: Kissinger. He may have been to more parties this inaugural week than most people attend in several years. This is not an exaggeration.

Rich: Betsy Bloomingdale, well-known friend of the first lady. She is extremely thin, and wore a shimmering green strapless dress that made her look even thinner. She also talked with Ted Graber, the first lady's decorator, who was one of those wedged into the inaugural ball at the Kennedy Center.

Somebody asked him how it was.

"The ball?" he said, then rolled his eyes upward toward the ceiling.

By 2 a.m., stragglers like Alejandro Orfila, secretary-general of the Organization of American States; Roy Cohn, New York lawyer; and Charles Wick, co-chairman of the inaugural, were finally leaving. They piled out into the lobby of the Fairfax Hotel, where people like Andy Warhol, party-goer, and Hugh Carey, governor of New York, were just arriving.

But not for the party. Warhol was just having a drink in the bar, and the governor, who's a Democrat, said he was in town on business. This had to be so, because he was one of the few males in evidence, including the waiters, who didn't have on a tuxedo.

But he seemed to enjoy the surrounding furs and jewels. "This presidency has a flair about it," he said. "Although Washington remains a temporary stopping place for people who have not found their destiny. The capital has a style. What it needs is character."

Then he disappeared into the plumage.