Billie Eilish Says She 'Cried' and 'Threw Up' Before Hosting 'SNL' : 'I Didn't Feel Qualified'

Billie Eilish served as both the host and musical guest on this week's episode of the NBC sketch comedy show

Billie Eilish is reflecting on the "full-body reaction" she had to starring on Saturday Night Live.

The Happier Than Ever singer, 19, visited SiriusXM's The Howard Stern Show Monday and told host Howard Stern that she cried and threw up ahead of the sketch comedy show over the weekend, during which she both hosted and performed.

"The week preparing for SNL is f--- nuts. It's literally alien. I mean, I cried every single day of the week, no joke at all," Eilish recalled on the radio show. "I did actually love to act when I was a kid, but that's not my world so I don't know what the f--- I'm doing. I feel like I'm terrible, I feel like I suck."

Eilish added that the "craziest part" of her week was Wednesday's table read with the entire cast.

"I was just scared. It's SNL. It's these amazing, talented actors surrounding a table where somehow I'm the main course for this show I didn't feel qualified for," she shared.

Stern, 67, then told Eilish that he didn't notice she was nervous on the show, specifically during her opening monologue, in which she joked about growing up in the spotlight and the media scrutiny over her appearance. But the seven-time Grammy winner admitted that she was actually "petrified" of what people would think.

"I was ready to throw up — I actually did throw up because of it," the "Bad Guy" singer laughed. "I had a full-body reaction to being anxious about this the whole week. Threw up on the plane coming here, had crazy s---- when I got here like you would not believe."

Though Eilish had an extreme physical reaction to her nervousness, she said she instantly felt relieved the moment she walked out and felt the audience's "joy," which allowed her to have fun.

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Juggling duties as both the host and musical guest for the latest episode of the NBC sketch comedy show, Eilish delivered a powerful performance of her song "Happier Than Ever" from her second studio album (which dropped on July 30) in between sketches. She was also joined by brother Finneas for a haunting performance of "Male Fantasy."

This was Eilish's second appearance on Saturday Night Live. She previously served as the musical guest for the show's season 45 premiere in September 2019, which was hosted by Woody Harrelson.