*yike*. Yes. That sounds very definitely threatening, and quite a lot like one of the drills my self-defense class did a lot. Instincts are there to be trusted. I'm glad you're okay!

(fwiw, what we did in the drill, when someone was walking behind us and it felt menacing, was stop, spin around, and either yell "Back off!" or go right into a fight depending on what they did. If this guy was mostly enjoying making you scared and the sense of his power, staying put and yelling could well have worked. But since I've never had to try it for real...)