Very cool and tough prototype!  I like the second level!

One issue I found was that when the player is against a wall it doesn't seem to allow the player to shoot.  Then later in the second level the bullets appear to be the same color as the floor and are only visible in shadow.  While the game is perhaps too challenging atm, I'm confident that with some fine tuning of the mechanics (like the players movement drag) that this game will be a lot of fun!

Many things (UI, dialog, level design, etc) in the game work very well! Awesome work making a playable prototype! Cant wait to see you take this further!