I Have Severe Pain On My Left Side. It Is

I have severe pain on my left side. It is a stabbing pain. Goes to my back also. What could it be? I had to have a bladder sling put in and a few months after that I ended up with bladder cancer. Could this pain be from something like the spleen or possible pancretatis? I also have colitus and problems with my kidneys. I am just a mess. This hurts so bad I can not take a deep breath. What should I do?

I am sorry for bothering you. I have no money.