Welcome to HCM.
Don't worry.You can continue this treatment but give this tablet with some light food or with some milk,don't give her empty stomach.
Stomach pain might be due to infection inside.It will recover within next 3 to 5 days.
You can give rebeprazole or pentoprazole with domperidone
to subside stomach heaviness.Avoid oily,junk food,take more liquid diet
will be helpful.
Ask your doctor and keep in touch with doctor.