She rolled backwards into your car...you swapped details as you were going to ring insurance to claim...then realised your car wasn't sufficiently damaged to warrant the hassle and you didn't really see it as a problem...??

If she hasn't got medical back up for these ''injuries'' shes royally bolloxed anyway...
& Not reporting this incident that caused these ''injuries'' ?!!
& No inspection

If somebody gave me whiplash, (a condition that would prevent me driving home and meaning i might need to go to a&e for some sort of neck brace) I'd be straight down the police station

Don't worry about it...just don't admit to anything