How many have ever had Food Poisoning really bad ? I've had it really bad once , but I've unfortunately had it three times.
Usually the last thing I had to eat in my mind got labeled as the culprit , when it truly wasn't.

Once really bad & I had eaten the same as friends who didn’t get sick at all.

Same with me the very first time . We were on a camping trip and everyone had the same thing.

Mine was in Goa/India & we all ate from the same dish...all cooked, no salad, no ice in our drinks, knew the rules & do’s n don’t of what to eat & not eat in India. Luckily there was a doctor holidaying at the resort who came to check on me & he got me to eat a banana every hour for potassium & drink salt/sugar water. I was fine within 24 hours. It felt like a purge on an epic scale.
Every other time I was in India from then on, I put Olive Seed oil drops in my water daily which is good for clearing parasites & never got sick....that is also a good product to use if you do get a stomach bug, it clears it up quickly!