I fell and hit my head and since i have had a headache and dizziness when i turn my head or get up.

Head injuries: Are important to identify. Though most bumps to the head are just a transiently painful unpleasantness, sometimes a mild concussion can result. All this depends on the mechanism of injury, so clinical assessment afterward is a good idea. Even "minor" concussions can have clinically significant consequences. Dizziness from inner ear problems can also be trauma related. See an MD for evaluation ASAP