My neice had a problem with gluten which they identified by cutting out gluten around 1 due to explosive nappies, tummy cramping and her growth stopped. She had some testing which was inconclusive to determine if it was an allergy or coeliacs, they wanted to give her a chance to 'grow out of it' before invasive surgery to test properly. So until she was about 3 they just stuck to 100% gluten free - she was also sensitive to cross-contamination - until the specialist felt she was old enough to 'test' on gluten again. Thankfully she did grow out of it.
I know the things my brother/SIL found hardest were the 'hidden' gluten products (eg. soy sauce, some brands of rice crackers), cross contamination (especially at daycare) and other people's attitude that 'a little but won't hurt' ... thanks, but they're not the ones who needed to deal with days of screaming after!
You'll probably need to become a bit of a compulsive label checker and re-check labels every few months as ingredients do change. Watching my neice's experience I agree with PPs, go GF asap regardless of where you are with diagnosis espcially if you can already see the change.