Why is he doing this?

The guy that I use to like and still do but just a little bit… well when we first meet in p.e. we would like hug and talk to eachother and he would hold my hand… and do all these really cute things and I heard severl times that he liked me so I wrote him a note telling him how I felt and asking him how he felt but after that day he never mentioned it… the next week on thursday I asked him t go to the movies with me and a friend and another guy friend and he smiled and said sure.. after that I was sooo super excited! and he told me to give him the information like when and where the next day so I was like ok… on friday I was like ok so I told him the time and place but he was like ohhh sorry I didnt forget but I have to get help from someone and they are leaving tomorrow so I cant go and I was like its ok… and it didnt bug me much… but what does bug me is he sees me in the hallway and looks right at me be doesnt wave, smile, say hi.. and he doesnt hug me anymore :( whats wrong with him why is he doing this to me?