Same thing happened to me when I was ten year old and left a bloody mass.Called your man a ****er and cycled on as I was in a competition,finished in a respectfull top 20.
That's a bad injury odd dog - I am very wary of 'parked' cars and try and keep three feet away at least. .....buggers. ....
Thought I'd given him plenty of room but it was a sort of mini-van and he flung the door wide open. Thing is, I had no idea there was anyone in the car - didn't see him pull up so he must have been sat in the car for a while ....................
that's almost deliberate or at least reckless, but that's the thing with motoring, they often act as though the only road user is a motorist, pedestrians cyclists and others shouldn't be there.. .....