What are his feelings towards me? I'm getting mixed signals.?

He is a junior and I am a sopre. We met through friends this school year. We started talking almost everyday, and sometimes on facebook. He would usually start the conversations, and what intruiged me was the fact that being his usually outgoing self, he would sometimes stutter and couldn't keep eye contact that well, and he always smiled when he saw me. I never see him talk to many other girls for as long as me. Everything was going very well when suddenly, he started ignoring me. I hadn't changed the way I acted around him, I wasn't flirty or overbearing or anything. I got frustrated for the way he was acting so I deleted him from my friends list on facebook. We usually go to the same area to hang out during lunch and sometimes when he walked over when I'm there (i'd started ignoring him too) he'd call out loudly some girls name and go over to hug her, all the while looking over in my direction towards me. He's single, and I know he isn't flirtatious with anyone, that's all he does to that girl, a hug, and my friend has said that when i'm not there at lunch that day that he doesn't even acknowledge that other girl. I hadn't asked her to tell me this since she doesn't know my feelings towards him. We don't have any cles together, but we always have to walk by each other in the hall because his cles always seem to be next to mine and he always finds some excuse to wait for me but completely ignore me along the way to cl. I really miss talking to him because he is such a great guy and I really don't know what happened, and advice on what I should do and what his feelings might be towards me? I still say hello and he always says hi to me and we smile at each other but after that he walks away...