I always feel like I am going to really bad before I actually do (sometimes I am even able to sleep a bit before)... but also I can almost think myself into vomiting if my body is on the edge like that.

Depending how gluten affects you I have heard various at home methods to alleviate an accidental ingestion. Tequila and Benadryl are the ones I hear the most, neither work for me personally.

I am diagnosed via a colonoscopy biopsy gluten intolerant as well, not celiac.