Re: 9 month old w/ digestive issues (long)
If your son is gluten intolerant, chances are he is also dairy intolerant. These two often go hand in hand.
The doctor needs to do the test for gluten intolerance ASAP. This is no joking matter and there is no cure. It's a lifelong commitment to eating without gluten. You need to start reading up on celiac disease in the internet. Even if you think you are eating gluten free, chances are (in the beginning because of misinformation) you are not. Almost all processed foods contain some type of gluten and even the TINIEST of amounts will set symptoms off (if that is the problem your son is having).
If your doctor can't check for celiac disease get a different doctor. I can't believe that he suspects it but leaves it at that!!
Rice is the one grain that that usually does not cause allergies/intolerances from my understanding. However this information may be outdated as these things constantly change.
I would also suggest you stop breastfeeding him, if you still do. If he's intolerant to ANYTHING you are eating and it's a strong intolerance he's going to have a reaction. You need to get a doctor to check for celiac disease. If that comes back positive you neeed to check for dairy intolerance. THEN go from there.
Anyway, best of luck to you.