JB's ex-gf has reportedly partied too hard at the Vanity Fair Party, says Radar Online's unnamed source.

According to the report, Sel did not waste time by boozing up the night and allegedly drinking champagne and other light liquors such as vodka and gin.

"Selena was drinking constantly throughout the entire party when I saw her," spills Radar Online's source. "She was having a grand old time and towards the tail end she was stumbling in her heels and almost toppled right over," continued the source.

Although the alleged source claims to have seen Sel partying the night away, the former Disney star was not photographed with a drink in her hand, notes Mail Online. She did, however, posted a photo of herself all cuddled up with friend, Vanessa Hudgens on Instagram.

"@vanessahudgens my only, official party buddy for life ;)" she captioned the Instagram photo.

"Selena and Vanessa were just having a really good time, laughing and taking pics," the unnamed source told Radar Online. "She wasn't slurring too bad, but was definitely in the happy-sleepy stage."

The drinking spree comes after the 'Come and Get It' singer was rumored to have spent a couple of weeks at Dawn of the Meadows, a recovery and rehab facility in Arizona. As previously reported, Sel was rumored to have been admitted for Ambien and Xanax abuse, as well as emotional troubles with her nasty break-up with the Biebs.

A photo of the singer reportedly taken the morning after her alleged excessive drinking posted on Mail Online, shows a very sober Selena Gomez. The star is seen dressed down in the photo - with sneakers, pants, a sleeveless top and shades while clutching a red polo shirt.

"The day after the party, Gomez looked just fine - as in she didn't have a hangover - as she headed to a dance studio in LA.," the Mail Online report remarks.

Did Selena Gomez really got very drunk at the Oscars party?