A nervous Adele has premiered her "intimate" new single, Hello, on BBC Radio 1.
The singer said she was "going to belch" as breakfast show host Nick Grimshaw cued the song up.
"My hips just started hurting, as I'm getting so nervous," she laughed. "There's a heartbeat in my hips for some reason."
"I obviously want people to like it," she said, describing the song as "very intimate" and "very conversational".
"I'm singing very high up in that chorus, trying to have a Meatloaf moment or something."
A simple piano ballad with a soaring chorus, Hello was first teased during an advert break on Sunday's edition of The X Factor.
Adele said she was worried people would think the 30-second clip was simply a new advert for John Lewis.
"I thought no-one's going to know it's me. It'll backfire," Adele told Grimshaw.
Asked if she felt any pressure after the success of her last album 21, the star said: "Because of my last album, because of what it went on to do, it was kind of a write-off to ever expect anything with this album, the new one, like that. So actually it made it a bit easier.
"Getting into the headspace was really difficult - obviously now I'm a parent, and having such a break off, I kind of fell out of the habit of writing songs.
"So no I didn't feel pressure. But also I feel like every album I'm ever going to write is always going to be following 21. Even no matter what this album does, my next record's going to be following 21.
"It's phenomenal what happened with that - but it is a phenomenon. I can't really include it in any expectations of anything I ever do again."
A video for the song has also been posted on the singer's YouTube page.
Analysis: Mark Savage, Music reporter
Musically, Hello doesn't rewrite any rule books but it's a powerful, moving reminder of Adele's ability to pull at our heartstrings.
It begins, like Someone Like You, with Adele's lone voice over a mournful piano figure. But by the coda, the song soars - with a vocal flourish that sends shivers down the spine.
The lyrics are a simple apology for breaking someone's heart. Throughout the song, Adele repeatedly tries to get in touch with her ex, but no response comes. By the end, her regret is tinged with bitterness with that her transgression "doesn't tear you apart".
"It's so typical of me to talk about myself, I'm sorry," she sings in the second verse.
Somehow, I don't think anyone will mind.
The star's comeback comes after three years of musical silence. Her last single was the Oscar-winning Bond theme Skyfall in 2012. Her previous album, 21, was released a year earlier and went on to become the biggest-selling record of the 21st Century.
Thanks largely to the success of the emotive ballad Someone Like You, the record sold more than 30 million copies worldwide.
In the UK alone, it shifted 4.75 million copies, making it the country's fourth best-selling album of all time, in an era when album sales have been in critical decline.
The follow-up, 25, has now been scheduled for release on 20 November.
Explaining the gap between albums, the star, who had her first son, Angelo, in 2012, said: "I did pretty much write an album about being a mum but that's pretty boring. I scrapped that.
"I felt like I was never going to finish this record, she added. "It was a long process. I wanted to give up a lot because I couldn't do it. I thought I'd run out of ideas and I'd lost my ability to write a song.
"My team around me are so amazing. They're very honest. They were like, it's not good enough. Go back to the drawing board.
"It didn't hurt me at all. I think it's important that people are honest with you like that."
In a statement earlier this week, the Grammy award-winner said the songs were inspired by a "turning point" in her life when she became a "fully-fledged adult".
"My last record was a break up record and if I had to label this one I would call it a make up record," Adele said in a statement. "I'm making up with myself. Making up for lost time. Making up for everything I ever did and never did."
Not much is known about the sound of the 11 tracks that make up the album, but the star has reportedly worked with Danger Mouse (U2, Gnarls Barkley, The Black Keys) and Ryan Tedder (Beyonce, Adele's Rumour Has It), and Max Martin (Britney Spears, Taylor Swift).
The new single is produced by Greg Kurstin, whose previous credits include Lily Allen's The Fear and Katy Perry's Double Rainbow.