Yes and no.
If you wrote him in all caps I see why he didn't respond. No one likes reading that.
Persistence is okay up to a point, like just to say umm, hello? Past that is a no-go.
Personally, I wouldn't give a shit if I were you. I haven't looked at your profile, nor do I know you, but there are just too many people to get upset over one, or I guess several.