The game is pretty great gameplay wise, but could do with a little more information such as how damaged the enemies are, what exactly is going on with the grenades, more info on how exactly the fan works, etc.
I'm also not sure if it was purposeful, but while i know your health is linked with your ammo, it seems to take longer to charge the less health you have. I would think that's how you have it linked, to represent less ammo, but it doesn't work too well gameplay wise. Since your attack then translates to your movement, in the long run your health affects your movement, meaning the more hits you get, the harder it is to try and avoid more hits. It might be better than instead of more hits taking longer to charge your attack, it instead weakens your attack, that way it isn't affecting your movement.