Shy guy keen or not? ?

I have a group of friends I hang out with and I have a sneaky suspicion that one may have a crush on me. Hes a shy guy not towards his male mates tho but towards women. Hes quite insecure I've noticed. We have been hanging out for a couple of years but just lately I'm really noticing things. .. maybe I'm just reading into it.... So I thought getting someones oppion may help I must start with he has a girlfriend! But when she's not around I've caught him in the corner of my eye looking in my direction and no there's no one else around me so I'm pretty adamant its me. This has been happening for a while now Ive tried to catch him out he just looks away and then looks at his feet?? Another thing I notice that when ever I dissappear to do something when I come back he asks me where were you sneaking off too... which is probably nothing but I don't usually get asked that by other guys. There was one time he was over at mine hanging with some of his mates (my male room mates which I met him through them) and I was inside he came in and sat and chatted with me I was like you don't have to feel like you need to chat with me your right to hang with the boys. He ignored me and just talked about nothing really and was sitting rather close as soon as the boys came back in he moved away from me the boys said what are you doing in here and he didn't respond just said oh I better ring my gf and walked outside. And the other night I was on my phone for a while at his place walked in and saw him dissappear around the back and I then saw him looking around where I was on the phone looking for someone. .. i know i must be just paronioid! oh one more thing sometimes he just ignores me doesn't make eye contact or talk to me...hot cold hot cold! lolI'm not interested in him I'm just trying to figure it out Oh and his gf is quite attractive and im just an average jo! so I wouldn't even know why he would be interested in me!thanks!!