Jessie J has been readmitted to hospital with fluid on her lungs

Jessie said on Instagram: "6 weeks post surgery and I was back in the same ward I was after my surgery. Not expected or planned.

"I had and still have symptoms that pointed towards a blood clot on the lung. IT IS NOT A BLOOD CLOT THANK GOD.

"They ran a lot tests, which ended up showing I have an infection (still trying to figure out what) and a little fluid on my lungs.

"Finding it hard to breathe in, but I discharged myself last night (I hate being in hospital) and will continue the investigation as an outpatient. (sic)"

In a separate post, Jessie admitted that her recovery has been a mental and physical challenge for her.

The chart-topping singer wrote on the photo-sharing platform: "I know many people who will have gone through this or similar may or may not agree with me on this or not, and that's OK.

"But I know for me, the true hard journey of this whole thing physically was the day I went into surgery. The recovering physically is far from quick or easy, and mentally it's been the most challenging time for me.

"Especially as a Mum with a toddler and being unable to be the mother I usually am.

"And having to change the plans for my career for this year has been frustrating after working so hard to get to the point and excited to do it all. But it's life. I know that.

"And don't get me wrong, getting the all clear was an is incredible, but that result didn't speed up or make the recovery from the surgery any easier physically. (sic)"

Jessie also revealed that she's struggling to slow down amid her recovery.

She said: "That slow pace has been a hard reality to accept tbh. I love moving and working and being up and active but I can't be right now, and that's what it is. (sic)"