Always love a little puzzle game. Difficulty is alright, not too difficult yet not too easy, graphics is cute, and music is not overwhelming for a puzzle game too, good on that! The game is quite well polished, so there isn't much to critique, except it would be a bit annoying for the requirement to drag the bullet in place after a while. It doesn't add much to the gameplay or have some special action that required dragging in the first place, I'd suggest just pressing the button would suffice. I also ran into a bug where pressing back send me to the main menu, and I lost all progress on that :(
Other than that, it's a job well done. if it was more developed with more levels and mechanics, I could easily see this small puzzle game selling in steam and I would definitely buy it. Probably its me having a soft spots on good puzzle games. Good job!