Presently you are not having loose motion.. only stomach pain ..
And you are under treatment for some skin problem... Right...?
As per mentioned steroid (betnisol) causes Gastritis.. acidity .. which might be responsible for stomach pain in your case.
Next Steps
Start tab Nexpro 20 once daily empty stomach for 5 days.
And take betnisol tab after meals.
Eat at short intervals.
Avoid oily, Spicy food
Health Tips
Please consult Physician in person for Physical check up and needful investigation... in cases you are not better or develop other symptoms...