Brief Answer:
You will need to check

Detailed Answer:
Dear patient,
I understand your concern.
Upset stomach can be from simple gastritis, caused by foods, medications (such as the anti inflammatory ones you have been taking), smoking, alcohol or chocolate, and it can also be a more concerning condition such as chronic gastritis which may develop into a stomach ulcer. This can all be treated with a change in diet and PPIs treatment such as omeprazole.
What concerns me the most in your description, is that you have an autoimmune thyroiditis. This has been known to be associated with autoimmune gastritis.
And that's why I recommend you to have a specialist assess your condition thoroughly.
For the moment, you can take maloxx or other ph stabilizers for the upset you have.
I hope I have helped you!
Manoku Eni MD

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