What physiologically happen to create the sensation of an upset stomach?

I have an upset stomach. What is going on inside my body to create the feelings of fever, tummy tenderness, and loose bowels?
Answers:
irritant stimuli in the stomach lining, which is innervated=connected to nerve cell with pathway to brain, which sends impulses back to source of irritation, results within inflammation=pain, "spasms", etc; electric signals, releases inflammatory markers; simplified ur body will try to "purge" the irritants = diarrhea, fever, pain, within a nutshell...

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