Hi vickyi. 

I should start out by saying that I'm not a doctor. 

You are wise to be aware of your colon, and you have done everything right so far. But please be reassured that colon cancer is incredibly rare at your age.  

You've been diagnosed with IBS. Me too! One thing about IBS is that it can definitely make you want to pass motions multiple times per day, and repeated wiping can make your backside very sore, or bleed. I think (as you suggest) that the blood may be coming from a tear or a couple of small hemorrhoids.  One way to tell is to finish wiping and then hold a clear sheet of toilet paper against your anus for a few second and see if there's blood on it. If there is, then try with a second clean sheet, and if the blood is still there then it's probably coming from a tear or hemorrhoid - which is uncomfortable but not serious.  Your doctor may be able to prescribe a topical ointment that can heal the area and relieve any pain.