Would it creep out my crush if I said "happy birthday" on his facebook wall?

I like to be nice and say happy birthday to everyone. He very well knows I like him. He gives me this kinda serious/mean look on his face whenever he stares at me.He already has a girlfriend. So I think he might hate me. Should I or do you think he would block me?Don't get me wrong I have no intention on getting with him at all.
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+1 y
Sorry for spelling facebook wrong . I meant to put an "e"
Would it creep out my crush if I said "happy birthday" on his facebook wall?
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