This is really cool, the art and music are great, and there are a lot of cool ideas here. The concept of building the level around you to both make the game harder and screw over the enemies is a really compelling one.
The visual presentation of everything overall is really good, although I think having more feedback when you take damage or hit enemies would really take it to another level (There were a few times I checked my health and realized I was on 1 heart without noticing I had even taken any damage). I also think, with how this game is structured, fixing the camera so that you always see the entire room would make it feel a lot better, then you could tween the camera over to the other room when you enter them. As it stands now if your near a wall you can get hit by traps/enemies offscreen while most of your screen is taken up by empty space.
Overall though, great job! I really enjoyed this one.