What does this mean he hasn't called me in weeks?

i spoke to him about a month ago and he said he'll call me later. we weren't fighting or having an argument. he calls from 10 different numbers. i'm 19 btw we've been hooking up alot this past few months we've kept it discreet he doesn't want people to know what we've been up to. HE was the one who made the first move not me....what could this mean.?