I hope you got - or will go get - your jaw (and head) checked up. There might a lasting injury, or one that's really slow to heal, that you can avoid with proper medical attention. If anything, it will give you peace of mind.

Multi-use trails can be dicey. I sometimes use the one by our river at night: I have full lights on. The other night, I just barely made out a cyclist wearing dark clothes, on a black bike, with no lights and no reflectors. And then there are the walkers who of course absolutely have a right to use the path, but seem to forget that there are OTHERS on the path too... and walking four abreast across both directions doesn't help either!