Brief Answer:
needs further evaluation

Detailed Answer:
Hi,
I went through the query and understood your concern.

Abdominal cramp and bleeding per rectum with acute onset may be due to intestinal infection and this will also be associated with other symptoms like fever or mucous in stool.
Considering your age and bleeding per rectum you need to get evaluated for the cause. You need stool examination, abdomen and pelvis scan and colonoscopy. This will clearly diagnose the cause and helps in right management.

For now take plenty of fluids and antispasmodic drugs like dicyclomine will help in reducing the abdominal cramps. Don't strain yourself while defecation.

So in summary you need further evaluation.

I hope this information helps you. Feel free to ask for any further queries. I will be glad to answer them.

Wish you good health and faster recovery.
Regards

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