Bright red blood on the toilet paper, covering the stool or in the toilet bowl, indicates bleeding source located in the lower parts of colon and rectum.
This bleeding can happen due to presence of external or internal hemorrhoids (internal hemorrhoids aren't painful and the only sign of their presence is usually a bleeding), anal fissures or tears of anal lining of anal canal and anal opening due to straining and passing hard stool.
Another causes could be bleeding from colon diverticula, polyps and presence of enlarged, abnormal blood vessels in colon lining.
If this symptom is associated with diarrhea, severe cramps, fever you'll need to be checked for colon inflammation disease.
Colon cancer may cause bleeding, but it isn't its main feature.
At your age hemorrhoids should be checked first especially if you suffer from chronic constipation or chronic diarrhea.

Best wishes!
Marija