What is going on with my son?

Hi, I need some help. I have crohns disease, had 1 resection and after 7 years it is back. I have a great GI. My question is about my son. He is 14, 6'2", 220 pds. He has always had a sensitive stomach. As a child If he ate too fast or drank too much while eating he would throw up. But this hasn't been an issue for several years. He still takes what he calls tummy breaks, eats a little and waits, then eats more. Recently he started having twisting pain below his belly button, threw up when he ate and had diarrhea. In a 2 week period he lost 13 pounds. So GI has him to the radioactive eggs to see if his stomach emptied too fast or too slow - was normal. Also did an upper GI, small bowel follow through, didn't find anything. He did a Colonoscopy and scope to his stomach. GI found h-pylori in his stomach. We treated that with antibiotics etc. Son got better. Played football in school. Was doing great for several months. Now the pain is back, nausea. It is so painful he is not able to stay at school all day or he can't even go. I know he is in pain. We have him on Bentyl which seems to help some, but still has the pain. GI doesn't know what to do. He thinks it might be stress related (but everything is stress related, lol) and doesn't know what else to do. He even suggested taking my son to a psychologist to be evaluated. My son doesn't want to go to a shrink, says he won't talk to a stranger. Son says he isn't stressed about anything. My son has several learning disabilities, but he has never had this type of issue because of that. I feel helpless. I want to fix him, but no one has a clue what to do. I have tried changing his diet doesn't seem to make it worse or better. I need your help - what else can we test for? If you have read this far, thank you so much. Any help would be appreciated.