Brief Answer:
Chronic gastroenteritis.

Detailed Answer:
Hello and Welcome to ‘Ask A Doctor’ service.

Have gone through your details and I appreciate your concerns.

See most likely you are suffering from chronic gastroenteritis.Untreated infection has caused swelling in intestines causing pain.
Gastroenteritis refers to infection of mucosa layer of intestines and gut by bacteria and protozoans.In many cases its viral also but viral enteritis is self limiting and does not recur usually.
Initially i would suggest you to go for a stool routine and microscopy test followed with ultrasound of abdomen.
Long term untreated infection causes inflammation in intestines and hence causes pain nausea;incomplete digestion of food leads to formation of gas (hydrogen sulphide)which causes severe bloating and belching.

Rx
Tab Ciprofloxacin 750mg twice daily
Tab Metronidazole 400mg thrice daily
For bacterial and protozoal coverage(take a course of 7 days its a prescription medicine).

For nausea take Zofran 4mg twice daily(both are over the counter)

A pre and probiotic should be taken along with medicines for minimum 2 weeks post recovery.This will improve the overall digestion.
Take light boiled and easily digestible food.
Drink lots of juices.

Hope I have answered your query. Let me know if I can assist you further.
Regards,
.................................................................

Brief Answer:
Follow up answer.

Detailed Answer:
Hello again,
As Ct scan is normal and stool test is normal possibility of E.coli infection is there.
E.coli is normally present in intestines but some times due to rapid multiplication of the bacteria or infection by a mutant strain may cause such problem.
Have you been prescribed any medications(antibiotic) at that time by your gastroenterologist.
Awaiting your reply.

Take care,
Dr. Ramesh Kumar

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