Did I mess it up for good?

Ok, so I have a crush on this guy and last week my cousin and I went to a bowling alley. My crush was there and I tend to lose focus on anything else when he's around, so...yeah, I didn't play well at all lol But anyway, at the end of the event, my cousin and I were talking to a friend and my crush comes up to us cuz he has extra pizza and do we want any. I say no bc I'm running late and turn around and leave but when I get back to my car my cousin tells me he was looking right at me and was opening his mouth to say something RIGHT WHEN I TURNED AROUND. so...I don't know, I feel really bad about it and I sent him a message on facebook to apologize and he says it's ok, he was just saying hi, but it's just really unlike me, normally I'm this complete chatterbox who everyone wishes would shut up but I see him and it's like I forget I'm capable of speech, I can't say anything :( I don't know, does it seem like I ruined it by making him think I'm this weird, rude, antisocial person?