Rumor has it that Selena Gomez went heavy on the booze at an Oscar Awards after party, despite recently admitting herself into a rehab facility. An insider told Radar Online that the singer was drinking and even stumbled in her heels by the end of the night. The eyewitness said, "Selena was drinking constantly throughout the entire party when I saw her. She was having a grand old time and towards the tail end she was stumbling in her heels and almost toppled right over!" The source added, "Selena and Vanessa [Hudgens] were just having a really good time, laughing and taking pics. She wasn't slurring too bad, but was definitely in the happy-sleepy stage." As previously reported, Selena voluntarily attended an Arizona rehab facility back in January for two weeks of treatment.