Thanks for playing!
Reloading and a few other things can be upgraded by buying perks in the game. Each perk can be found in a room near the starting room. One of the main reasons why I decided not to use particles was that early on, I found shooting too many bullets or hearts could freeze the game and prevent more from spawning, so if I added particle effects, it could've made things a lot worse. However I will definitely consider adding it if its stable enough to be added.