Head injury - concussion ?

My girlfriend suffered a sharp blow to the top of the head yesterday afternoon. It's been about 20 hours since then and shes slept alot.

At the time she was in great pain, and saw a black flash, but didnt pass out. She's had a pretty much constant headache since, and says her eyes hurt, and she feels pressure..

We went to the ER yesterday evening after the hit, and they did an X ray (not CT) of her head, and sent us home, with her to be woken every 2 hours or so.

Anyway now shes had a good nights sleep and says she feels still horrible and lots of pain in her head, and eyes. She's also a litte nauseous.

This sounds like straight concussion, but form what ive read concussion tends to be mainly dizziness, but her main problem is pain in the head. Is this ever normal? And should I seek more medical help for her from maybe a different doctor?