A 12-year-old boy is brought to the Emergency Department after being struck on the head by a cricket ball travelling at high speed during a school match.
Since the injury, he has had 3 separate episodes of vomiting.
On assessment, he is alert with a GCS of 15 and has no focal neurological deficit. There are no signs of an open, depressed or basal skull fracture.
According to NICE head injury guidance, what is the most appropriate next step in management?