Respected user, hi I evaluated your query thoroughly.
* Certain informations are lacking here as - type of pain like burning,colicky ,
   radiating anywhere else , frequency , aggravating , relieving factors - food
   pattern - 
vomiting - bowel movements - LMP ?
* In absence of those details , we can conclude as 
gastritis - maintain her hydration with plenty of liquids
- avoid all oily / spicy / non vegetarian stuffs
- 
antacid tab. on empty stomach morning & evening helps 
- offer her light diet in small quantity at regular intervals
- take her to doctor if needed for evaluation in form of 
Ultrasound & further
  management
Hope this clears your query.
Welcome for any further assistance.
Wishing her fast recovery from the same.
Thanks for using Healthcaremagic.com & reviewing my answer.
Regards dear take care.