I know why you are having very dark sand like diarrhea
! The answer is PeptoBismol !
It is very common for people to rush to the doctors about dark stools and many times
they forget to tell the doctor ,they had used pepto. Other causes of dark stool include
slow bleeding in the stomach from small ulcers or inflammation from acid damage or
from medications such as aspirin
etc. As for your upset stomach, it may
very well be related to something you ate or drank.If you continue to have stoch
pains you should seek doctor's advice and undergo x-ray or endoscopic exam.