Can someone unblock when they blocked?

[Paris]

we wasnt friends to begin with on facebook we just messaged but we into it and he somehow blocked me but i was never his friend on facebook .then i gets back on and look in my messages and see that it no longer says facebook user and that it says his name so what does this mean? Can you block someone on facebook even if you was never they friend on there? Did facebook the system unblock me or did he unblock me?? And why do you think he unblocked me just to be noisy prehaps? His an ex boyfriend