Jessie J gave an emotional 2-hour performance Wednesday night just a day after her miscarriage. Jessie says she found out about the devastating news when she went for her third scan and was told the baby did not have a heartbeat. Jessie showed up in L.A. for the acoustic show at The Hotel Cafe, and told the crowd "I decided to have a baby by myself and by a miracle it worked for a while and yesterday it was f***ing s***." She went on ... "This year has been hands down the hardest year I've ever had to get through I lost my baby and I know I'm going to be OK. As for how she mustered the strength to put on a performance, she answered that before the show, saying, "What I do know is that I want to sing tonight. Not because I'm avoiding the grief or the process, but because I know singing tonight will help me. Before the show, Jessie posted, "I started singing when I was young for joy, to fill my soul and self-love therapy, that hasn't ever changed and I have to process this my way," adding, "I want to be honest and true and not hide what I'm feeling. I deserve that. I want to be as myself as I can be in this moment. Not just for the audience but for myself and my little baby that did its best. She ended by saying, "I'm still in shock. The sadness is overwhelming. But, I know I am strong, and I know I will be ok It's the loneliest feeling in the world.