Thanks for writing your query.
It seems that your symptoms are due to gastritis
Pain killers cause gastritis due to increased acid production. Therefore pain killers should always be taken after meals along with an anatcid.
You can take antacid
150 mg along with Domperidone
Antacid in gel or liquid form is also beneficial as it forms a protective layer over the damaged mucosa of the stomach.
You should follow some precautions like :-
1. Avoid spicy and oily foods.
2. Donot miss a meal.
3. Avoid cigerette/alcohol.
4. Avoid gas producing foods like peas, legumes, cabbage, etc.
5. Drink atleast 8-10 glasses of water daily.
If the problem persists, get yourself examined and investigated clinically.
I hope this is helpful to you.