Interesting...he made time to have sex with you.  Please don't take that as an insult.  It sounds like this guy enjoys the pursuit.  He got his goal (sex) and now it isn't as "fun" anymore.  You aren't as much of a priority as you used to be because he there's less to chase after.  His ego has been fed (for now).  This would make me think twice about wanting to continue anything with this person.  i wouldn't contact him again.  I suspect that as soon as you stop contacting him, he'll come back around.  Whether you want to contine something with him is up to you.