Jennefer Hirshberg, Nancy Reagan's press secretary, showed yesterday how she handles reporters who overstay their welcome. She shoved three of four reporters gathered for a spur-of-the moment interview with the author of a musical featured at a luncheon Mrs. Reagan gave in the White House East Room.

Later, calling to apologize for "the misunderstanding," Hirshberg said, "I honestly don't think it was a shove. I think I just tapped some people."

The so-called misunderstanding occurred at the end of the first lady's annual luncheon for Senate wives, which included excerpts from "Teddy and Alice," a new musical based on the lives of President Theodore Roosevelt and his daughter, Alice.

In thanking the cast, Mrs. Reagan called the musical "wonderful" and said she hoped the "rumor" was correct that the play will start off at the Kennedy Center. Jerome Alden, author of the book, was seated with several Senate wives at a table near the press area. As the other luncheon guests were starting to get up, reporters caught Alden to ask him about the play's Kennedy Center prospects.

"Okay, come on, let's go girls. Mrs. Reagan is going to be leaving," Hirshberg interrupted Alden and reporters from United Press International, the Associated Press, USA Today and The Washington Post. Of the group, only USA Today's Jeannie Williams remained untouched.

Mrs. Reagan wasn't anywhere near and the reporters were listening to Alden. To press her point, Hirshberg gently shoved three of the reporters, breaking up the interview.

"I've been sitting here thinking that I have to be more flexible," she said later when she telephoned her apologies. "I wasn't trying to keep you from talking to him."

In her apology to UPI's Helen Thomas she said that "the basis for making that decision was the other guests, so they could enjoy the occasion. I was only doing it in the interest of the event."

Thomas, who has been covering the White House since the Kennedy era, later described the eviction as being "pulled out like we were a bunch of kids -- scoundrels."

Susanne Schafer of AP said she thought the incident was "uncalled for because we weren't creating a disturbance. We were just seeking answers to some basic questions which Miss Hirshberg had not provided when asked earlier in the day."