Brief Answer:
Yes, he needs to be evaluated by a doctor

Detailed Answer:
Hello

Thanks for the query.

Symptoms following head injury can be mild to very severe. In most of the cases symptoms follows immediately after head injury, but sometimes patient can be remotely symptomatic.

Apart from loss of consciousness, vomiting, abnormal movement, altered sensorium; the discharge from nose(clear or bloody) is also an indication for evaluation by a physician.

As in your case it is mild and occurred after 3 hours of injury, the chances of any severe injury is less.

I would suggest you to be on the safer side; get him evaluated by a doctor and to rule out any injury to skull bone or blood vessels by clinical examination and investigation if needed.

I will be glad to answer if you have any further query
Wish your son good health
Regards

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