Thanks for writing your query.
After reading your post, I would suggest you following investigations :-
1. Liver Function Test(LFT).
2. Serum Amylase and Lipase.
Your symptoms can be due to excessive acid and gas production.
You can take antacid
20 mg once a day before breakfast.
Following precautions can be helpful :-
1. Avoid spicy/oily foods.
2. Do not miss a meal.
3. Avoid cigarette/alcohol, if any.
4. Avoid emotional/mental stress.
5. Do not self medicate, especially with pain killers and steroids
Reports of the above mentioned investigations will help in planning your medical management.
I hope this is helpful to you.