Brief Answer:
A detailed below.

Detailed Answer:
Hi.
Thanks for your query.
Noted your history of gastritis since teenage. More vulnerable when there is excess gas in stomach with all the symptoms you have noted; passing of gas or fart.

This means we have to concentrate on gastritis, and gas formation.
The commonest causes are as follows:
Increased acidity or no acidity due to medicines or disease.
Stress and anxiety/tensions
Chronic intestinal infection.
Certain foods and beverages form more gases.
Aeophagia- meaning swallowing of the air inadvertently.

I would advise you the following:
Upper GI endoscopy and Colonoscopy.
Ultrasonography to start with.
Tests of stool on 3 consecutive days.
Tests of blood: routine, blood sugar, liver functions, thyroid functions and so on.

- Make the list of the factors that cause or increase your problems. This includes all the foods, liquids, snacks and all; also contains other factors like tensions, stress and all.
Once the list is made you have to strictly avoid all these factors. In medical field
prevention is better than cure.
- Now make a list of the similar factors that do not cause any problems.
- You need a sound sleep of 6 to 8 hours.
- Morning exercises help a lot.
- Rest of the treatment as per the reports of investigations.

I hope this answer helps you to get a proper early diagnosis and an effective treatment based on the proper history and investigations.
Till then you can start with Multivitamins and probiotics, exercises.

Please feel free to ask for further relevant queries if you need to or if you feel that there is a gap of communication.
I shall be happy to see the reports of the investigations you asked for and discuss further to assist you the most.

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