Over the last few days I have been feeling a sharp pain in my left lower abdomen. Its been on and off during the day. No problem with bowel movements but it still feels like I have to go. Just today however I did see blood in my stool but it was solid stool. I retain water because I am on predisone and take a water pill once a week. I read that it could be a dehydration problem as well. I would appreciate any insight.