Lady Gaga may be one of the world’s biggest musicians, but she can very well still be intimidated. In fact, she was so nervous on her first day of shooting “American Horror Story: Hotel” that she vomited in a plastic bag in her Rolls Royce on the way to the set — and handed the bag of puke to show co-creator Ryan Murphy.

“I threw up in the plastic bag and I saved it and brought it to Ryan Murphy,” Gaga told reporters at a press junket on the set of the FX horror anthology Wednesday. “He was like, ‘Oh, you think you can disgust me? You can’t.’ The thing is, you think you can’t get anything past him, but then he met me. And I’ll bring him a bag of my own vomit to the set.”

For Gaga, who plays bloodthirsty fashionista the Countess on the show, “AHS: Hotel” marks her biggest foray into acting yet. She joins a cast of bucket-list actors, including Kathy Bates and Angela Bassett, so she immersed herself into the role and “prepared [her] ass off” before stepping onto the set. “All I have is my preparation time and Jesus, really, to save me from possibly screwing this up,” she said.