My son has been almost crying in pain for about 2 hours with belly pain. He's saying it's around the belly button and straight down and across his belly like in line with his pyjama waste band both sides. Can't be his appendix there gone with a few years. He hasn't been sick yet but feels it. Any ideas what it could be. Just waiting on a call from 111. All I can think of is he ate late tonight. He says it comes in waves and is burning. Can also taste sick. Nothing like this has happened before. Help please