Can I accuse this guy of stalking me?
Who is stalking you?
I think this man is stalking me
It's better to be safe than sorry, so you should confront the man first before reporting him.  It's not wrong to accuse someone of something, but you shouldn't report him without evidence because it might make the situation worse.
I have a bulletin board in my room that will prove he is stalking me.
If you ever find proof that they are stalking you, then you should definitely accuse him. Until then it seems to be something that the police wouldn't exactly take seriously.