A 12 year old boy presents to the clinic with vomiting quite a bit for 6 hours.  He has vomited 3 times, it is non-bilious and non-bloody in colour and not forceful. He does not have any reported abdominal pain. He has voided 3 times today and has had one normal bowel movement. Earlier this morning he was playing soccer and was struck by another player. There was no loss of consciousness. He sustained no obvious injuries.

Physical Examination: He looks tired.  Abdomen is flat. On auscultation, bowel sounds are normal. On palpation it is non-tender and there are no masses or organomegaly. The remainder of the physical examination is normal.