I'll keep this short and snappy. A re-ocurring problem I had post-gf diet was 'why do I feel so rough when I felt so good initially'. After hounding my GP repeatedly and proving I'd been a good Coeliac (cue blood tests, 2nd endo, camera pill), it appeared that nutritional deficiencies aka Iron, Vitamin D were to blame. Plus problems digesting certain sugars (including those in my prescribed vitamin D tablets!).
I know that many other Coeliacs on forums often feel rough despite being strictly gluten free. Often Drs can't advise on how long it takes to feel better (once stomach heals etc) from years of gluten damage. There's often mixed info online, 1 year - 3 years to feel better? Whilst research on CD has come a long way it can be frustrating and disheartening as a patient if all your hard work doesn't appear to be paying off. So if you are silently worrying why you're not skipping along the gluten free road or your child seems to have dipped since going gluten free do read this article. It's from the Aussie Coeliac Society and is truly the best explanation I have come across. It covers the FODMAP diet, sugars, IBS response time to healing and other great insights.
I hope that sharing it helps you feel better and can lead to some useful discussions when you next have your Coeliac check up. Let me know if it mirrors your experience.
See: Click on June's mag > Why is the gluten free diet not helping me?