Diagnosis

On Thursday, Foodgoat bought a jar of peanut butter.
On Friday afternoon, Foodgoat had a peanut butter and jelly sandwich.
On Friday night, Foodgoat came down with some extremely uncomfortable and painful gastrointestinal symptoms.
On Saturday, Foodgoat was miserable.
On Sunday, Foodgoat was better. But had no desire for a peanut butter sandwich.

The FDA and the peanut butter manufacturers say that jarred peanut butter is safe, but that jar of peanut butter will remain untouched while I google "salmonella test kit" ...