chachi,

You son needs to take it a bit easier. No more video games or highly stimulating TV watching.

Has his soccer coach taught him heading the ball? Do they practice it?
This could have conditioned his brain to be much more sensitive to impacts.

The clinic doctor is clueless. He should be held out of strenuous activity until his symptoms are resolved. 2 days is not going to make much difference. Consider 2 weeks as a starting point.

If he skis and is learning snow boarding, he will be much safer skiing. The risk of further injury is much higher from snow boarding with the frequent butt plants that transmit impacts all the way to the head. Skiing in a sedate style with no racing or mogul jumping should be easier on his brain after his nausea resolves. He should go easy on the risky activities for the next YEAR.

The young brain is extremely active growing and maturing. Head injuries during this age can lead to lifelong problems.

Hope you family doctor has a clue about concussion. Most don't.

My best to you.