M.,
It sounds like it could be food poisoning. My friend got that about 3 years ago when she went to Mexico on vacation. She was put through the ringer as far as testing went. They found an intestinal "worm" in her intestines.
She had the same symptons as you!
It might also be that your body is more sensitive than the others at the wedding and your symptoms lingered.
Probiotics are excellent if you have the "right one"! I have crohns disease and the probiotic I take every day has kept me in remission for over 6 years. Didn't happen over night, of course...but with time...I can now eat normal again! Feel awesome and like I say...am feelin' great.
Check out different doctors until you get answers. That's what I did. I have had the pain for over 25 years and my "family doctor" back then used to tell my mom that I was over-reacting! That I was a hypo-chondriac. It wasn't until in my 30's that the pain got so bad and my doctor had retired that I found a new doctor and they actually did the "right tests" and found the culprit.
Just keep seeing doctor's until someone finds the answer.
My heart goes out to you! It royally sucks have to watch what you eat, where you eat (being close to a bathroom)...
Oh!! Do not eat anything sugar free! It's a diaretic! It'll make you go twice as bad! Learned that by accident! LOL! ;-) I can laugh now...wasn't so funny at the time!
Lots of love to you and your family,
I'll keep you in my prayers!
J.