I had stomach virus which gave me horrific stomach pains / cramps for 10 days and was constantly in the bathroom. No vomitting though. I think you would have more severe symptoms if it was colon cancer my freinds, or any cancer.... Loss of weight.. not 5 pounds, more like 50 pounds in a short period of time, dark blood in the stool, etc. This isnt what sounds like you have and you are too young for that I believe. I am being a total hypocrite.