It was a bit confusing to understand you need ammo packs to reload, it took me a while. Tip: I see you got mixed art styles like pixel-art, hand drawn-like pixel art and abstract shapes. I suppose it's because you started in one style, but didn't have enough time to finish everything. Try to stay consistent with your style, I personally go with abstract shapes. It makes you really think about and spend more time on the game's feel and design. Extra tip: there is easy tool to generate sounds for your game very fast, here: https://sfxr.me/