Really cute game, If I were to give some feedback, I think the character would control way nicer if you added some coyote time (after you step of a ledge, you still have like half an second to jump), and maybe a bit more control to the jump, so that how long you press it for, determines how high you jump.
Also a bit more gradual difficulty curve would be nice, as the game starts with some really tight jumps. it's pretty easy to get stuck at the begging, stopping the players from exploring the game further.
But i'm just nitpicking here, for your first game it's really solid.