This may mean something in your GI tract is bleeding, which could be anything from a ulcer to haemorrhoids or something more serious. Any time you notice blood in the toilet bowl, see your doctor, especially if it doesn’t look fresh. Certain medications can turn your stool black but the colour is temporary and harmless.
Very loose stool, but not diarrhea
This could mean you have celiac disease or you need to reduce the amount of gluten you’re consuming. Cut down on your high-grain diet to aid absorption and firm up your stools.