Yep, I recall when I got my knee bashed in by two thuds I was still able to walk and run. I felt the inital snap then a bukle where I took an immediate fall, but survival kicked in and I got up to walked back to my car. I could have almost ran. It wasn't until an hour later when the swelling kicked in that I cannot stand and ended up leaving ER with crutches. It amazing how the body can response in certain condition. If I'm not mistaken I think the body also releases some chemical similar to Morphine when we feel pain.

If I was to ever confront anyone in a bike related incidence, I will at least tell them to get out of their car first and level out the disadvantage. Then it's a warning for them to back off. If they don't comply, then it is Taser, Fox 5.3 spray and Kimber pepper blaster time. Once they are out of their car approaching you after a warning, I think that's more justified as self defense.