So, for some months, maybe one week a month ill have constipation and blood in my stools. I often get a sharp pain coming from my rectum which makes it uncomfortable to sit and lie down also but this goes away after a day or two. I have read up on lots of posts about colon cancer and fissures and what not and from what others have been saying that it would be rare for a 20 y.o. to have colon cancer but is not impossible. The blood appears to be bright red most of the time. It also often hurts to wipe after i have been to the toilet and i often have blood. Any suggestions as to what it may be? I have started to take a fiber supplement to see if that makes it go away. Could i just be tearing something what i go to the toilet which is causing the bleeding??