I did much the same yesterday. Out to lunch with friends - and the 1st course was filo pastry. As they'd made such an effort and it would be rude to refuse to eat it - I just got on and ate the food. Refused the base of the cheesecake though!
However, I had a rotten night with all symptoms of a severe cold and have spent half of this morning in the bathroom.
But a day or two of eating "clean" again and I'm sure all will be back to my new normal!
I couldn't help observing, though, that all of the other people at lunch - early sixties, just a bit older than me - were on all sorts of medication for high blood pressure, diabetes, pancreatitis, lupus and severe depression! The conversation was very medical biased, and while they all ate wheat products happily but took pills, I could tell that I was considered "faddy" for not wanting wheat - but was the only one there not on any medication!!!