Fun game! I don't think the difficulty is a problem, but the fact that you can take instant damage when you enter a room makes it seem way harder.
Some feedback: You could make specific enemy layouts depending on which door you enter from, so you never have an enemy near that door. I would also suggest a small delay when you enter a room before the enemies activate, so you have a tiny amount of time to take the layout in before you start to run. Make the enemy and player sprites flash a color when they take damage, to make it feel more impactful, also maybe a small screenshake when the player takes damage.
I really enjoyed the game, and with some more time and tweaking I think it could become a blast to play :D Well done!