Great first game, i found it fun.
One thing that would help a lot is having a way recheck the current level objectives and hiding areas, if you skip them too fast and could not remember, you have no other way to access them gain other then restarting the game.
Also, sound design is something simple that would be help a lot the game experience. Take some free sounds, and attribute it to certain elements or situations. A great thing to do most of the time is to have multiple similar sounds and decide randomly which on to play at certain moment.
The only thing that I dind't like that much was not in the game it selft, but on the fact that (at least for me) it doesn't look to fit the theme very well.