Why do guys act interested one day and not the next ETC.?!

I am 27, and HATE GAMES! I like this guy and at first he was shy and then he talked to me, and he asked a LOT of questions about me, even if I have a BF. Some days he acts interested some he doesn't and I DON'T UNDERSTAND. Yesterday he was practically laying on me in class and today he ignored me completely! I am so confused!
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+1 y
Thanks. He goes back & forth on showing interest! What can I do to seem more responsive?!
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+1 y
Also to clarify... I DO NOT have a boyfriend. He asked me if I did and I said no,. Because I dont!
Why do guys act interested one day and not the next ETC.?!
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