i was sitting in a chair with my computer on my lap when all of the sudden, it felt like my head jolted down like something hit me square in the middle of my dome. i lost all control of my upper body (dont know about my lower body as i was sitting) i thought it was an earthquake but i was the only thing moving. i thought perhaps my laptop had given me a good shock but that was not it. i had never experenced anything like it. if i was standing i would have definatly hit the ground like a sack of patatos. i was conciouse the whole time. it seemed like the ground shook back and forth and up and down all at once. do i need a cat scan? or can it be an ear infection cousing disbalace at an extreme level? only happend once