However, those watching a live stream of their set online could see how Jesy had become upset after they’d finished their first track.
Jesy later posted on Instagram, revealing that she’d had a panic attack and bandmate Perrie Edwards had stepped in to cover her part on their rendition of Falling.
Sharing a video of them rehearsing the performance, Jesy wrote: “So my nerves got the better of me today and I had panic attack right before we were about to sing this for live lounge today and like a pro @perrieedwards jumped in for my part last minute and smashed it.
“This is what we originally did in rehearsals.”
Jesy has spoken candidly about her struggles with anxiety in the past, and also fronted a BBC Three documentary, Odd One Out, about the effects social media trolls have had on her mental health.
Useful websites and helplines
Mind, open Monday to Friday, 9am-6pm on 0300 123 3393.
Samaritans offers a listening service which is open 24 hours a day, on 116 123 (UK and ROI - this number is FREE to call and will not appear on your phone bill).