I'm about 90% sure they gave me food poisoning in December on an MCO-LGA flight. The meal/beverage that I had on the flight was all I had had to eat that day, and symptoms manifested almost exactly 4 hours post-meal - unfortunately for the guy beside me, on my next flight.

Viruses don't usually cause that particular reaction, or at least have not in the last 25+ years since I was 12 and under (the last time I was sick like that).

I pinpointed it to bad creamer in my coffee, as it had undissolved floaters (at the time, I thought it was powdered creamer.

Good luck. It's a miserable experience.