How to be sure if DS has a problem with gluten?

[Looseleaf]

I can't tolerate any wheat nor DD and we both have very clear symptoms if we eat any even if it took us years to realise the problem.
DS is 3 and very tired physically (no 'natural' energy to run about and like dd did asks to be carried a lot) .
He's been on a largely gluten free diet but not 100% as doesn't have the strong symptoms we do apart from tiredness/ constipation so I'm really not clear if gluten is the issue. He's once broken out in clear bumpy spots after a normal Danish pastry and apart from getting constipated he can have quite unsteady moods but I can't be completely sure if he has a problem with gluten (and he used to be dairy intolerant but I don't think is any more).
Is there a reliable way to be sure i can find on the nhs as a pin prick test showed nothing for dd or I ? We were offered a biopsy but by then it was so clear gluten was out for us I felt no need.
Is it otherwise just a food diary ?

I really want to be sure on what's best for his diet before starts school in case it's stopping his energy. Thanks so much if any experience to share

My daughter and I are Gluten free also - I notice her behaviour is really bad if she eats gluten and she gets bunged up. We are also cow's milk intolerant - generally low energy, constipation, rashes and sinus problems. None of these have shown up on the skin prick test, yet I know we're much fitter and healthier without them. Unfortunately there's been no other way apart from elimination and food diary to identify these problems. But I'm happy to keep them out of our diet as we all have so much more energy generally and DD does not turn into the tazmanian devil!

It can be a pain when we're out and about at friends etc. but at nursery they put on a Gluten / dairy free menu for my DD and other children so she never feels left out which is good.

Thank you so much and I'm so impressed with your DD's nursery- DD's used to organise cake etc without me knowing ahead so she never had anything!
It is so good you know and I think I'll just try a strict food diary then. Thanks

As you are almost there already, could you cut gluten completely for 2-3 weeks (see if you notice any change) then, if the changes you observe haven't already given you your answer, reintroduce it and see what, if any reaction you get? Any reaction should be much more noticeable when he has been off it for a couple of weeks than it is when he is having gluten here and there consistently.

I think that's a great idea. Thanks. We've managed well today with boiled eggs, gluten free oat cakes etc. so I'll make sure we stay as strict as DD and I are to see