L.
Hi!
It sounds like he is ready to make the move to a big boy bed! It is not too early--my son moved at 16 months to make room for the new baby! He transitioned just fine and never even tried to climb out! I set it up first and let him get in and out and try it for a day or two and then he asked to sleep in it and that was it! Not hard at all!!
Good luck!
L.