Hello,
1) Yes this is bleeding from intestine which react with enzymes and turn into maroon-brown colored.
2) Presence of blood increase bowel movement ad that is why you might have passed black colored stool frequently
3) You should go to ER rather than out-patient clinic for such bleeding episodes as it may look small episode of bleeding but actually it bled inside intestine and it might have enough blood loss to make you weaken, tired and lethargic
4) All your symptoms of
dizziness,
headaches, body aches were associated with bleeding episodes
5) First thing to be done is to stabilize your overall condition, i.e. after checking your
hemoglobin level if require then transfuse blood, if you dehydrated then start IV fluids.
6) Once condition is stabilized then plan for
colonoscopy (there is chance that doctor could not find any reason for bleeding due to loaded intestine with stool and blood clot). To avoid this possibility cleaning of bowel is advisable if overall general condition of patient is good (to avoid
dehydration)
7) Most common causes for such bleeding episodes are diverticulitits, ulcer, tumor growth. And taking any medicines for thinning of blood (Aspirin) is aggravating factor to initiate such bleeding episodes