I Have A Sharp Constant Pain On My Left Side

I have a sharp constant pain on my left side flank area. Went to the ER and they said my urine and CT scan were normal. Pain is worse when laying down. I can also feel something popping when I take a deep breath and the pain when I cough is bad enough to bring me to my knees. Could this be kidney stones or something wrong with my pancreas perhaps? Pain has been going on over two weeks now