pain in the belly button area

I have had this pain in my belly button area for a year. The doctors don't know why. I get the pain when I have to have a bowel movement. Even before I have to have a bowel movement. Even when I don't have to have one. The pain is always there. I have been to the hospital, but they don't know what it is. It makes me sick. I get such pain that it makes me cry. I don't like to go the hospital anymore, because they don't do anything for me. Sometimes I can't even move or get out of bed. can someone please help me. Thank you.Monica