Singer-songwriter Jessie J was rushed back to the hospital six weeks after undergoing breast cancer surgery, citing complications involving fluid on her lungs, according to a report by Daily Mail.

The 37-year-old artist, who previously shared that her cancer was caught early and successfully operated on in June, posted on Instagram over the weekend that she had been readmitted due to troubling symptoms.

“How I spent the last 24 hours. Six weeks post-surgery and I was back in the same ward I was after my surgery. Not expected or planned,” Jessie wrote in an Instagram Story update Sunday, accompanied by a photo showing an IV cannula in her hand.

She added that doctors initially suspected a blood clot in her lung but have since ruled it out. “I had and still have symptoms that pointed towards a blood clot on the lung. IT IS NOT A BLOOD CLOT THANK GOD,” she said.

Instead, Jessie revealed she has developed an infection, leading to her hospitalization. The artist admitted the past few weeks have been “the most mentally challenging time” of her recovery.

The singer, best known for hits like Price Tag and Domino, first revealed her cancer diagnosis earlier this year, crediting early detection by her doctors for catching the disease before it progressed further.