Is he losing interest?

My current boyfriend used to be so excited for hanging out with me and he was always very admiring. He is younger and shy, however, so I am usually the initiator and I usually don't expect him to initiate himself. Recently, however, whenever I ask him to hang out he says he's busy some way or another and I haven't seen him but 30 minutes in the last three weeks! I also usually text him every day and feel welcomed, but now it seems as if I am a nuisance. So my questions are- Could he actually be THAT busy? Is he losing interest in me and just too shy to break up? orr Am I just being insecure?