WATCH: Selena Gomez Reveals First Legal Drink She Had

Selena Gomez just turned 21 on Monday, but the former Disney star is already spilling the details of her birthday celebration!

On Wednesday, Gomez made an appearance on Late Night with Jay Leno and revealed what she had for her first legal drink. "I had a shot of Jack [Daniels]," she told Leno.

Gomez also told the Late Night host that she's planned a big birthday celebration for the upcoming weekend, since her actual birthday landed on a weeknight.

"We're going to have little skirts and things to put on, henna tattoos, belly dancers," she said.

Go to page 2 to watch SelGo on Jay Leno!