I think when a werewolf attack an human he become vampire...
And yeah vidhyud is yet to be born?? So strange i think maybe werewolf grow more fast than human and vampire grow less fast than humans, for Preet i donno i felt she had become younger than 4 years before, the purple dress(Anita was looking beautifull) and her hair is less long, yeah she had maybe cut it...
Anyways the thing i do not THINK and i am SURE of it is that dhara love vivaan she go to shearch him n when she called preet i think she was crying...