Hit head on car 4 days ago, dr said evaluation was good, no ct scan! i'm still dizzy and some headache! no sickness or didn't pass out ! is this norma?

Post-concussive Synd: Had a mild concussion and now have symptoms of a post-concussive syndrome that should get better within six weeks.

Concussion: You may have sustained a concussion. CAT scan in this case will not show abnormalities. Typically symptoms should subside within 1 to 2 weeks. But if you have persistent headache and vomiting, then consult with your doctor again.