Think I may transfer to secondary soon, since I don't want bottle bombs.
transferring to secondary won't prevent bottle bombs. if there are sugars in there that the yeast can still eat, they will eat them. going to secondary will decrease the yeast population so it'll take longer... but they'll get to it eventually. so if you transfer, you're increasing the chances that there will be sugars left in there when you bottle - and increasing your chances of bottle bombs, unless you secondary for a really long time. hence, you shouldn't go to secondary until primary fermentation is complete.
just because it's bubbling doesn't necessarily mean that fermentation is still happening. the beer could be off-gassing, reacting to changes in temps or atmospheric pressure, etc. have you taken gravity readings recently?