Dear user, Of one thing I am quite sure: the vaccine did not cause it. The most likely causes of upper abdominal pain (i.e., related to the area of the abdomen where he has pain) are stomach acidity, muscular catch, inflammation of the liver or gall bladder, or a psychological event. Please review his diet and make sure he is on a healthy diet free from excessively spicy or acidogenic stuff. You need to take him to a physician again and push for a trial of antacids and pain killers at the first instance; if this is not useful, request for an ultrasound and basic blood tests like a blood count and liver functions. The last step would be a counselling session at the school with the accredited psychologist if all physical causes have been ruled out. I hope this helps.