Hit my head about an hour ago. it was bleeding a little bit but it has stopped. i'm not dizzy. how much longer do i have to wait to sleep?

Response: Sounds like more of a superficial event causing either an abrasion or laceration. Depending upon the size of the area, if large and still weeping, you may need help with closure. Not knowing more, tough to advise whether a doctor should be contacted. But based upon your description, would not prohibit sleep if you are tired. Do bandage area, as rebreeding could occur during night.