The 'Liar' singer also took a brutal fall off stage -- but she's laughing it off.
The "Liar" singer performed several tracks off Romance during a special live show from Apple Music's New Music Daily held in Los Angeles on Saturday, and explained to fans during the event how Mendes fit into the upcoming record.
An eyewitness tells ET that Cabello, 22, performed multiple songs that alluded to her romance with Mendes, 21, and told stories to the crowd about how she's "so in love," but didn't mention Mendes by name. One of those anecdotes was about her and Mendes' first date and kiss, as the former Fifth Harmony singer recalled working on a song with Billie Eilish's brother, Finneas O'Connell. Cabello said she and O'Connell started working on the song, "Used To This," which came together just one day after her trip to San Francisco, where she and Mendes shared their first date and kiss.
According to ET's eyewitness, Cabello appeared really connected with the crowd and performed flawlessly at the Apple Music event -- despite falling on stage. The singer quickly recovered from the fall, and joked about it with the audience. "The one time I regret not allowing phones. That was funny as f**k!" the eyewitness says she exclaimed at the event, which didn't allow fans to bring cell phones. Cabello finished closing her set and said her heartfelt goodbyes.
Cabello later took to her Instagram Story to assure fans she was alright. "The rumors are true," she said. "I fell on my f**king a** tonight. Actually, I think it was the hardest fall I've ever had. It was about a six-foot, seven-foot fall. But I didn't feel it because the adrenaline was so high on stage that I could probably get hit by a truck and be like, 'Are you guys having a good time!?'"
"But thank you guys for asking. I'm totally fine and OK and actually thought it was really funny," she added.
Cabello's performance will be released before the album by Apple Music. See more on the singer in the video below.
Reporting by Nastacia Nickolaou and Clint Black.