I think Diane hit it when she said other intolerance's , after going Gluten free I found I had a corn intolerance and it made me bloat and gassy .... So you may want to do a food diary.
I think that there are other food intolerances that are "hidden" by the Celiac or the gluten intolerance. Like your body is working so hard to combat itself, in the case of Celiac disease, that it kind of fails to alert you to other problems. For example, I never had an issues with citrus, then suddenly, after a year of being gluten free I was (and am) allergic to citrus! I cannot have any citrus at all because the symptoms are like torture --burning, itching --no rash or eruptions, just terrible, terrible burning itching!
I am starting to have sensitivities to other things now (2 years gluten free)..... I really cannot help believing that my body, fighting the celiac symptoms, was "masking" other intolerances, allergies, and issues.
And: A food diary is an excellent idea!! I kept a food diary for 7 years and it helped me to figure out a lot of things!!