Oops, she did it again — and again — and again!

In an attempt to make her ex-boyfriend jealous, Britney Spears has been brazenly flirting up a storm in nightclubs — and she’s using her celebrity status to sidestep underage drinking laws, charge sources.

What’s more, she’s playing Russian roulette with her multimillion-dollar career, warn insiders.

One of the most shocking incidents occurred in her home state of Louisiana. The 20-year-old pop tart — who is seven months shy of the legal drinking age — was caught on-camera dirty dancing with a drink in her hand, and The ENQUIRER has the photos to prove it!

An eyewitness who was at Extra Innings, a club in Hammond, La. — only a few miles from where Britney grew up — saw her dancing, drinking and flirting on Saturday, April 6.

“Britney arrived at the club around midnight with a group of girlfriends,” he told The ENQUIRER. “The club has a full-service bar and no minors under age 18 are allowed in.”

Although she arrived dateless, Britney bumped and ground her way around the dance floor — sometimes sandwiched between two guys. Despite her wild gyrations, she managed to hold on to a drink.

Aaron Arteaga — a college student who danced with Britney — revealed, “It’s not a big deal to drink if you’re underage. All the kids do it.

“Britney had a drink in her hand when I was dancing with her, but I don’t know what it was.”

The singer, her cousin Laura Lynn and their girlfriends didn’t leave the club until around 3 a.m.

Britney’s wild flirtatious behavior in public has a definite purpose, a source close to the star told The ENQUIRER. “She’s out to make her ex-boyfriend Justin Timberlake jealous in the hope he’ll come running back to her.”

And she’s working hard at it. Just days before frolicking in Louisiana, Britney was spotted at two Miami Beach hot spots on separate nights — and there have been many eyewitness accounts of her allegedly drinking.

In the Sunshine State, an underage drinker can get burned with up to 60 days in jail. And in Louisiana, a violator is subject to up to six months in the slammer.

But Britney is taking an even bigger risk, warns top image consultant Maxine Fiel.

“Fans can be fickle and turn against celebrities who don’t behave according to the law,” she said.

“If Britney’s image becomes too tarnished, advertisers who use her for endorsements may yank her contracts.”