Should I Move On?

know every single girl on this earth is gonna have boy problems at least once in their life.. So here goes..I've been talking to this guy for quite some time, now, and things were doing really good like.. a couple weeks ago, then he starts being "busy" all the time, and not home or able to hang out or anything. He told me all the time how much he liked me, and how much he wanted to be in a relationship with me. That's why I don't understand how quickly he could change his mind. It's like he doesn't even want to talk to me or anything, and it's really heartbreaking. I don't know if I should move on or not, because I have this feeling that soon we will start talking again, and everything will be back to normal. Could you guys help me out?