help me understand boys

So I met this guy 4 or so weeks ago, we went on a first date 2 weeks ago and it was like a fairytale! Everything went so well and he said as he dropped me home, there's a party in a few weeks and you are going to come with me. We talk a bit the next day and say how much of a great time we had, but then the next few days he started to drop off a bit and I feel as though he doesn't want to talk... so I don't message him, 4 days goes past and I send him a text to see how he has been (it was strange to go 4 days without talking cause usually he would always message me writhing 2 days) we talk for a bit and the convo dies, we haven't talked in a week and I know I might sound crazy but it's not like him. My friend is also mates with him that's how I met him and she says he got a lot going on at the moment with uni and work as exams for uni are in 2 weeks..and he told a co worker who I'm friends with that he likes me but he  can't be anything serious because he's so busy. But why won't he talk to me about this??!  (Hes never had a relationship and same with me) he doesn't know that I know anything about with my friends have told me. So any help trying to understand him and for help on what to do would be greatly appreciated!!