I was put on iron tablets as my iron storage was low. Gp said it was low but I wasn't anaemic. She asked if I was losing blood. I told her not that I knew of. She asked me to hand in a stool sample. It came back positive and she is referring me for a colonoscopy. I haven't slept As I'm worried sick incase it's cancer. I have no other symptoms. What is the chances it is. I am 67 years old