The combat mechanism is something new, or at least for me, I like it. As several times already mentioned the player should be forced to leave the middle room, for example when staying in a room for too long a more dangerous creature appears, or if you still have motivation you could implement these powerups you spoke of.
The door is hard to access in the hurry, but maybe that's just me :)
The music sounds nice, but it fits to the sleeping girl, not to the dangerous situation of the incoming blob invasion :)
Great game anyways, keep up the great work!