I was driving to work on Interstate 5 headed north between Highway 33 and Bates Road I believe. There were no other cars around at the time and I had not seen any other aircraft before there was suddenly a large shadow passing over my car coming from the south west direction headed north east. That is what made me notice the object was the size of the shadow covering my car and how suddenly it appeared. Just as it was done passing over the top of my car I saw that the shadow looked like a large boomerang (if I had to compare it to a craft I know I would say it was almost like a stealth bomber) but it was hard to tell because I had to stoop down and crane my neck up to try and get a look. About then was when the bright blueish white light covered my car and blinded me slightly. I then had to try to focus again on the road but the light and aircraft stayed with me for about a mile I would say before the light stopped and the shadow passed back over my car heading back the way it had come from. I continued on my way to work but I still felt very disoriented and had a hard time focusing in general. My head felt pretty foggy afterwards like I had just woken up and my vision was hazy, like I was looking through a white lens and it was tinting my vision. Within ten minute my vision was pretty normal but I still felt out of sorts and slightly agitated. At the time I was about ten minutes or so from my destination but I arrived ten minutes after when I should have and I had a strong headache throughout the night while at work.