The High School Musical star makes her first appearance since getting a nose job
Credit: Peter Kramer/AP

Ashley Tisdale made her first public appearance Friday night since undergoing a rhinoplasty procedure on Nov. 30.

The High School Musical star performed at the Z100 Jingle Ball concert to benefit Autism Speaks at New York’s Madison Square Garden Friday, despite still having some pain and slight swelling from the surgery.

Tisdale reluctantly went under the knife to correct a severely deviated septum and have her twice fractured nasal bones (once from a car accident and once from getting hit in the face while dancing) realigned.

“I’ve known for years that I’ve had a deviated septum,” Tisdale told PEOPLE. It wasn’t until after the 22-year-old toured with High School Musical in South America last spring that she realized the magnitude of the problem. After performing her solo set, Tisdale exited the stage in a panic.

“I was so out of breath, I started hyperventilating,” Tisdale says. “They were thinking it was a heart attack. The [tour] doctor got me an oxygen tank and I sat outside the stage and breathed in oxygen until I could catch my breath.”

Tisdale enlisted the services of renowned Beverly Hills plastic surgeon Raj Kanodia, whose celebrity clientele includes Jennifer Aniston, Cameron Diaz and Ashlee Simpson. Kanodia determined that Tisdale’s septum was 80 percent deviated.

“If I laid down on my right side it was like somebody closed up the right side of my nose,” says Tisdale.

Kanodia tells PEOPLE he’s “ecstatic with the results. “Functionally her nose is better and cosmetically it’s better because I got rid of the effects of the [injuries].”

Now that she’s on the mend, Tisdale says she “never wants to have plastic surgery again.” Why so adamant? “I don’t believe in plastic surgery. I really think natural is more beautiful. This was not about changing me. I am comfortable with myself,” she says.