Thank you!! Great job finding all hearts! I am surprised multiple people managed to find *that one* heart to the left in particular.
The hearts are meant to be zero in the final battle since they're used up to boost your stats (I didn't have enough time to create a cutscene or any sort of indication of that happening unfortunately, but I think it was explained in the tutorial?)
Potions and bullets weren't supposed to be gone, though, so that was definitely a bug. But congrats on still finishing it :)