Very well-made, fun game!
Though just to let you know, I encountered a bug while I tried pressing x next to a wall (and possibly during collision with an enemy while at low health at the same time? I'm not sure):
"runtime error
player.state="againstwall"
line 733: attempt to index global 'player' (a nil value)"
Nothing major, I just got unlucky and I think I was basically dead on that frame anyway.