Well you certainly couldn't accuse Selena Gomez of being unprofessional. The just turned 21 year old gave herself practically no time to recover from her birthday celebrations with her pals before she turned up on The Tonight Show with Jay Leno show for an interview and to perform her new single Slow Down.

Phew, maybe she should take some advice from her own song title because we know if that was us, we would've called in sick with our heads leaning over the bed, trying our best to sound like we were almost dead. Then again, we tend to be a little dramatic sometimes.

Selena Gomez 

Nevertheless, not one to disappoint her fans, Selena chatted with host Jay Leno all about her birthday antics, which even though left her with a bit of a hangover, she said aren't even part of the real celebrations yet.

Blimey, just when we thought Sellers was a good girl she goes and gives herself a birthday *week* - something only mega divas do (and us of course). 

Watch the video for yourself and find out what drink S-Gomes chose to ring in her big 21 and the crazy cake she got from her friends...

Taco cake? A gypsy themed birthday party? Henna tattoos? Our birthday bashes usually just involve a trip to TGI Friday's and our dads embarrassing us in front of the fit waiter. Sigh.

Selena even changed into a racy black number for her performance of the single Slow Down. What a trooper.

What do you make of this then? Which are you loving more - Selena's performance, her outfits or her taco cake? Discuss please...

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Images: NBC