So much this... Despite trying to drive defensively I have been involved in two major car accidents. The first one I walked away from, but the second one put me on Flight for Life. Despite the accident itself being pretty bad, the only physical issue was a broken leg that took a couple years to heal properly. However the REAL issue took longer to realize -- something from that accident has caused me to have continued sleep issues since then. I'll be on medications the rest of my life probably, and even then I still have trouble getting restful sleep if I've been physically active.

Yeah it's easy to feel invincible when you're young, and your body can heal from a lot, but just remember that those things can also fuck up your shit in ways you might not realize until years later. Things you take for granted now (like sleep) can really screw up your enjoyment of life when they don't work right.