Great art, fun idea, I don't hate the puns - the intro was a bit long for my taste, wish I could skip the text as soon as I'm done reading, but I get that you wanted to set the mood.
My minor complaint is that I would rethink the note icons design next time. Internalizing which icon corresponds to which button takes time, and for a game jam game I would much prefer to have straight up "left right space" icons at the cost of stylization to avoid the frustration of hitting the wrong button. Remembering the spacebar was easy enough, but maybe you could move the arrow on the left key icon to the left of the gun? So that way it would be easier to make the connection "I click left when arrow is to the left of the gun, and I click right when arrow is to the right of the gun", and you maintain the stylization that way.