Coping after near-miss accident w/my son in the car. I'm so shaken up.

Had a very scary near miss accident this morning taking my son to school. A car was passing in a no-passing zone very close to my home and nearly hit us head on. We both swerved enough to avoid an accident, but it was a split second away from being absolutely awful.

I tried to hide my panic from my son and act as normally as possible on the rest of the way to school, but I was so shaken and scared, imagining what could have happened to my baby. Just that awful feeling of "what if".... and knowing that I can be the safest driver in the world and I still can't protect my babies from crazy idiots. This happened a few hours ago and I'm still physically shaking and replaying what could have happened in my head.

I know others have likely been through this kind of thing. How did you cope? Any advice?