What would make my stomach hurt whenever I eat?
Go to doctor
It could be a stomach ulcer. I had the same symptoms when I had one. Definitely make an appointment with a doctor to make sure, but in the meantime, drink plenty of water.
Try the ada app it’s accurate and it’ll tell you wether to go to the doctor or not.
Irrateable bowel syndrome
Could also be a sudden food allergy. At your age the culprit is usually dairy or wheat or both. Sometimes gluten but more often than not it’s just the wheat. Avoid all breads (this includes pastries, cakes, breading.. basically anything that uses flour..), avoid eggs, and switch to a lactose free milk such as soy or almond milk. I personally despise those plant based mills do if you do as well, use lactaid milk instead. It’s real milk but without the protein lactose in it. Give it two weeks. I am allergic to all three of these things so if I eat them I feel like I swallowed a bowling ball and feel nauseous for a few days until it all passes.
It could be an ulcer. Only a doctor can find out for sure.
I have pin worms and the same exact thing happens to me So maybe you have them too.