With her mum, nephew and Brother in law supporting her from the side of the stag, the 'Bang Bang' singer gave a flawless performance, despite being hospitalised for a mystery illness the week before.
During her set Jessie even admitted: "Doctors told me not to be here today."
The night before the festival, Jessie reassured fans she'd be appearing at Wireless, saying: "I'm out of hospital, still very fragile but much better. I will be at Wireless tomorrow. Not my usual crazy running around self yet but I will be there. Can't wait."
And the 'Price Tag' singer was clearly delighted to be back doing what she loves. Sharing a heartwarming message post-performance, Jessie said: "I felt so lucky to be on stage today. If you had seen me last week… No one in my friends and family thought I would bounce back for this show (inc myself) It took everything I had but I did it. I did it. Thank you."
Giving another update, Jessie admitted she wasn't feeling quite as bold as she appeared, telling fans: "You have no idea how nervous I was... I nearly fell over when I came out! thank you so much."
Jessie first revealed she was in hospital last week, choosing to keep the reason for her operation private. Although she did confirm it had nothing to do with her voice or her heart condition.
Revealing she was struggling, Jessie opened up to her followers, saying: "I am not ok... I am in a lot of pain. But I'm working on it with the doctors. We all have our moments and one of mine is now. Being human sucks when you are non stop and your body says NOPE not right now."
We're so glad Jessie J is on the mend, pretty inspirational stuff right?!
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