Most Helpful Guy
Serial killers are pretty fascinating if you look at their story. If he has a smidge of intellect, he wouldn't post something like that on facebook to hurt you. If he's a sociopath, his friends would all know if he hurt yu since he posted this publicly. Sociopaths avoid that at all costs.
So no, maybe he's a little bitch and stuff, but i wouldn't fear for your safety
Most Helpful Girl
No, sociopaths are usually extremely charming and alluring, they don't try to scare their prey until it's to late to escape. Unless you dated a dumbass, you should be fine.