I like this guy and I know he is probably attracted to me, because I saw him looking at me and his expression changes when he sees me. We started to talk and say hello to each other. He started it and it was fun. One day i was a bit tired, so I wasn´t so "enthusiastic" during our conversation and on the other day he acted cold and very serious when he saw me. Next day I said hi with smile and he started again. But everytime when he is with his friends and sees me, he avoids eye contact with me or turns back.. not sure what does it mean. I like him and I am interested to kno whim better, but I don´t know where I am with him.