My son was preemie ...he is now 4 years ..I have noticed that since three months he occasionally complained about stomach pain .last month I took him to ped he adviced some basic acidity medicine n told no reason n nothing much to worry. Now again since 15 days he is complaining of stomach pain, body pain..his appetite is not good ..eats only few quantity n getting weak..he will play and after that complaint to me of body sickness. I am unable to understand is he really sick or mood or tantrum.please advice diet for his stomach upset. Today he had constipation also