Brief Answer:
Please take him to the emergency immediately

Detailed Answer:
Hi

Thanks for asking on this platform

I can understand your concern. Based on severity of the condition I would suggest you to take him to the emergency immediately. Doctor will examine him personally to find out the cause of acute pain and also to rule out life threatening condition like entangled intestine, obstructed bowel, any gut perforation. Although these conditions are rare but must be ruled out in such cases. The doctor may advice for ultrasound also. Once the acute life threatening conditions are ruled out he may need some injectable analgesics to get relieved. Acute pain can be due to gastritis or infection also.
But here he needs to be taken to an emergency urgently.
Please let me know if you have any more questions.
Wishing for good health of your baby.
Warm regards

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