****** up dream/reality. Please help. Why do I feel pain when I dream?

You may have been dreaming that you were still awake. That has happened to me also. The pain you experienced in your back could have been a spider bite (I state this because once when I was sleeping I was bit by a spider but did not feel the pain until I woke) or your subconscious reminding you of your kidney failure and the need to be more cautious and aware of it. I have included websites on dreams and dream interpretations that may better help you understand your dreams.