Yes, you can still pursue a personal injury claim--filing a police report or pressing charges, which are criminal justice system actions, are separate from bringing a civil lawsuit.However, you cannot sue--or rather, you can sue, but will not get any money--simply because your "head hurts." To recover money for a personal injury, you need medical evidence of an injury, such as a diagnosis and test results; you will need a medical expert to testify (which can be very expensive); and the amount of money you could potentially get is related to the amount of out-of-pocket (not paid by insurance) medical bills you have and the provable extent of your injury. So if you have not yet been scene by a doctor and have any diagnosis of an injury, there is no action you can take.