Billie Eilish recalls her first TV debut at 15: 'I was very sick'

Billie Eilish opened up about her first ever television debut at the age of 15 at James Corden's show.

The Bored singer, appeared as a guest on The Late Late Show with James Corden on Tuesday for Corden's final week on the CBS talk show.

James, 44, asked Billie, 21 what she remembered about that day after showing a photo of Billie on his show.

"I remembered that I was very nervous,' Billie said. 'I was very sick. I was sick for many years, I feel like. Everything I did I was sick. My voice was kind of messed up and I was really nervous. I just wanted to do a good job."

"You are exactly the same person that I met then in your core and in your person," James said.

Billie also admitted that acting in Swarm was a dream role for her.

"Donald Glover is my all-time hero, lifelong hero," Billie said.

Billie further revealed that she had been making music in the studio in the basement of her brother Finneas' house.

"That's where we made the last record and then we've been doing it again,'" Billie said. 

"It's very different this time. It's proven to be different every single time. It's weird. Every time, I'm like I've got it I know exactly. How to do it this time, you know it worked last time, I'm going to do it again and I can never recreate anything."

Elsewhere in the interview James played a video clip from Lollapalooza, showcasing the crowd and asked Billie how she connects with that size of the audience. 

"You can't really,' Billie said. 'I love playing festivals. It's one of my favorite types of shows to do. It's just a sea. You stand there and it's just endless people."

Billie said she finds festivals harder and puts more effort into the shows.

"I like to go out on the thrust, which is the catwalk thing, and I'll look back at the stage and I will see myself on the the giant IMAX and it feels like I'm really at the show and I'm like in the audience and watching me on stage," Billie said.