A month ago 9 year old ds had a bout of gastroenteritis, or something similar, he spent 8 hours vomiting, with stomach cramps and headache. He went back to normal after a couple of days. 2 weeks later he had sever stomach cramps, so severe he was in tears and doubled over in pain, no vomiting though. After 2 hours as bright as a button as if nothing had happened. After 2 weeks exactly the same thing. 2 hours of stomach cramps and then totally fine. What can it be? A&E told us to go to gp and get a referral.