Brief Answer:
Possible food poisoning

Detailed Answer:
Hello,

It is possible that you have food poisoning, or possibly a viral gastroenteritis. Either way, the treatment would be the same, you can take something like bismuth subsalicylate for the stomach ache, and keep a diet that is low in fatty foods or dairy until this resolves. You may develop diarrhea, and only if you were to get fevers or blood in the diarrhea would antibiotics be recommended. If the diarrhea or stomach issues persist beyond a week, doing stool testing for bacteria and parasites could be considered as well.

I hope that helps, please let me know if you have any other questions about that, and I would be glad to discuss it with you further.
Thanks.

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