Brief Answer:
Give same acid reducing agent with anticolic

Detailed Answer:
Hi

Thanks for asking on this platform

I can understand your concern.
As you are suspecting this abdominal discomfort due to heavy eating, I think giving acid reducing agent like lansoprazole will help. The symptoms seems to be increased gas production.
Give plain diet with plenty of fluids at least for one day.
I think this will suffice but still if he is complaining of pain you may give anticolic like dicyclomine.
Watch for symptoms of food poisoning like loose stool, vomiting etc and if you notice any please contact your pediatrician.
I hope this helps.
Please let me know if you have any more questions.
Regards

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