Ugh, headlights! Those can be so horrible. Since I drive a small car, every time I'm in front of a truck the lights are right in my eyes. It's awful, but there's not much you can do about it in the side-view mirrors (or up front for oncoming vehicles). If only the side mirrors could be shifted to show a dimmer reflection of the street like the dashboard mirror can, heh.

Given the issue with headlights and the headaches/tension you get from looking at a monitor for too long, I'd say it's pretty safe to say you are 'photosensitive,' or visually hyper-sensitive. This can certainly be a part of SPD. I would recommend finding an occupational therapist (OT) who can work with people with SPD and see what their input is. They may be able to make a diagnosis and help with treatment options.

Welcome to the site though. I hope you find this place to your liking and are able to find the support you are looking for here. Thanks for posting.