Hi, I was diagnoised with celiac disease in junior high as well. I was really nervous about bringing my "different" food to school. My mom ended up taking me on a one on one shopping trip to find the best tasting gluten free food we could find (It was really fun.) When I faced my insecurity and ate at school, I was shocked to find that my friends loved the food. I think that because I felt so confident about the food my mom bought me, my friends were more interested in trying it. About the belching and gas, I experience that as well. I find that tums work really well. Also, flushing your system out with a lot of water helps you recover faster. I know how embarrassing these symptoms can be considering I am also a teenager. I wish your son the best of luck.