My gastro told me if the blood is dark red, then it is coming from the upper GI tract (stomach or small intestine) - if bright red, the large intestine. Wherever it is coming from, you really do need to see a gastro and find the cause, then you can get appropriate treatment. Any kind of blood in your stool is abnormal and warrants immediate investigation.
Take care,
Liz.
anytime there is blood in your stool you should notify your doctor asap