Does he like me? I can't tell...?

So there's this guy that I really like. He's a year older than me. Saturday was our homecoming and we went with the same group of people. At dinner, he sat right next to me even though there were a bunch of other chairs open (as well as tables). We played stupid games (tic-tack-toe and dots...) and he usually let me win. After dinner we went to the dance and most people went off and danced. I went and danced with people but later went back and hung out with him in the corner. He said that he danced with some girl and kept telling me that it was akward because he doesnt like her. at the end his younger sister wanted to leave and hes said no not yet. but they ended up leaving and at first he said 'bye sadie' and then he came back and said 'bye' to the group of us and then 'bye sadie'. does he like me? what should i do?