Brief Answer:
gastroenteritis probably

Detailed Answer:
Hello,

your case sounds like gastroenteritis, although other diagnoses cannot be excluded. It's just too soon to consider other potential causes that would fit with your description. Important points to clarify include:
- the presence of blood in the stool and the stool consistency
- constant abdominal pain particularly if the pain does not move around (if it's on a single constant location that is)

Blood in the stool may mean various things. Gastroenteritis caused by certain bacteria is one of them. Other causes may include gastrointestinal bleeding, inflammatory bowel diseases, tumors, etc.

In gastroenteritis the pain usually involves the lower abdomen and may move around or come and go. Peritoneal inflammation causes localized pain that usually gets worse with time.

So if you only have diarrhea and intermittent pain, you've probably got a gastroenteritis. Avoiding milk, fat and fiber may help to reduce the number of bowel movements (and the associated discomfort). Make sure you drink enough fluids.

If you get worse or you have any of the aforementioned serious signs then visiting a doctor would be recommended. For any acute diarrhea that lasts more than a couple of days, testing the stool for bacteria is recommended (stool culture and microscopic examination). Drugs like loperamide may help with bowel movements. Make sure you're afebrile and there's no blood in your stool though.

I hope it helps!
Kind regards!

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