What should be done for blunt trauma to the head?

ER : Er evaluation. Of course it depends on the details and force of the trauma. But if there is significant pain, particularly in association with any nausea, vomiting, confusion or disorientation would need urgent evaluation for concussion at minimum, internal bleed as worst case scenario.

Depends. : How severe? Did you lose consciousness? Are there lasting effects? Seizures? Headaches ? Lot more info needed. A neurologist may be best place to start

Many things: If you had a concussion, the symptoms should resolve on their own, usually within a few days, but may take months in some cases. Treatment is just rest and to avoid any further injuries. Its recommended not to stress the brain with activities, such as driving, doing homework, watching TV, get plenty of sleep too.