Earlier today I passed out when I stood up. My girlfriend said that I kept shaking with my eyes open. I regained consciousness after a few seconds, all that I remember happening were bright lights and a sense of euphoria. I've always had an issue with passing out when standing up but have never been able to recall shaking or keeping my eyes open during. I was also recently in a car accident in which I hit my head when the car flipped a few times which blew my ear drum. And I've also had major back issues since. I was wondering if the shaking and passing out might have something to do with the car accident.

My medical history is fairly clean except mental illness.