Anytime I walk into the room, he looks the other way. Is he nervous?

My friends and I noticed anytime I enter a room the guy I have a crush on will turn away.
For example, last weekend I was coming inside the house and he saw me coming in-but turned his head away. But when I went up to say hello, he looked at me and said "oh, hey!" like he didn't see me... lol

I also remember he did this a month ago at a party. I arrived and he immediately got on his cell phone. Rather than saying hello. But again, when I went say HI, he was fine.

Its weird because we've been friends for a long time...
Anytime I walk into the room, he looks the other way. Is he nervous?
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