Spears Calls Vegas Wedding Her Rebellion

March 12 -- Britney Spears said she was being rebellious, irresponsible and just plain silly when she spontaneously married childhood friend Jason Alexander in Las Vegas after a night of partying in January.

The marriage lasted just 55 hours before it was annulled, but the buzz surrounding the surprise wedding lasted far longer. The pop star spoke about her short-lived union to Alexander, a childhood pal from her hometown of Kentwood, La., in an exclusive interview slated to air on E! Entertainment Television.

"It was me being silly, being rebellious, and not really taking the responsibility of what I was doing, you know? And after partying, you know, you really don't think about what you're doing. So it was one of those things that were really silly," Spears told E!, as part of a two-hour special that will air at 8 p.m. Sunday.

Spears and Alexander reportedly traveled by limousine to the Little White Wedding Chapel on the Las Vegas Strip at about 5:30 a.m. on Jan. 3. When they arrived, the chapel staff sent them to get a marriage license. After obtaining the documents they needed, the couple — friends for at least a decade — went back to the chapel to carry out their wedding plans.

The 22-year-old singer wore a baseball cap and torn jeans down the aisle and was reportedly escorted by a limousine driver. By Monday morning, Spears was filing annulment papers.

"Plaintiff Spears lacked understanding of her action to the extent that she was of incapable of agreeing to the marriage," the petition said.

Time to Figure Things Out

In the weeks since the wedding, Spears says she has been able to put her growing pains in perspective.

"I think I was running away from something, I didn't quite know what," Spears said.