Why guys are so complicated? A men showed his interest in me but when i show them back they back off.?

Yes guys have no logic. They can like you one day and the next day never call you again for no apparent reason, even if they SAID they had a good time and want to see you again. All you can do is have fun and dont plan on anything going anywhere unless a man calls you and sees you several times. Dont call him or even bother trying to figure out why he gave you the cold shoulder. Its hard but you need to just take it out of your mind. Many guys are flaky and strange and all you can hope for is to find a normal one that wont play games with you. They are out there but you have to go through a lot of weirdos first.