You made this in a month? Holy crap that's awesome. The guns feel great, the sword is awesome. I fell into a pit and couldn't even damage a boss which was weird, but I restarted and continues on. Finding out you could "pistol jump" by shooting downwards felt neat, like an unintended quirk.
The screen shake was a bit much for me, and there wasn't much feedback on you taking damage. Some times I wouldn't even realize I was dead/dying until it was too late.
Other than that, you made an incredible game. Seriously. Well done!