For a month or so, I have noticed thin red blood lines in my stool. When I turned 50 five years ago, I had a colonoscopy and everything was fine. I do suffer from constipation, but I take medication that causes constipation. I have had some pain in my stomach area, but have suffered with that for my entire life. I have had bowel problems ranging from constipation to diarrhea since I was a teenager. I am going to schedule a colonoscopy, but must admit I am afraid that I may have colon cancer. What is your opinion?