That sucks! There is some machinery in there to prevent unwinnable states but it might not be (probably is not) 100% effective. Some spots you might check out: The grotesques in the first room, the statue on the balcony, under the bed, inside the casket (and the statue of Aeternitas), the feasting hall table, the urns in the ancient tomb, maybe the shelves in the laboratory, maybe the bricks on the roof.
This “machinery” works by transferring “leftover” attack power to unused weapons when you deal damage in excess of a monster’s remaining HP. If you can access the final boss, you should be able to access all the weapons, so the game should still be winnable—unless the power-transfer somehow sent some attack power to a weapon you’ve already used, which would be very stupid, but I *think* I prevented that.
On the other hand, before you unlock the final boss, the game could transfer some critical quantity of attack power to weapons gated behind the enemy who you need that attack power to defeat. The code is not sophisticated enough to prevent this. So it might be a problem.
If you restart the game, you’ll start at the beginning of the vampire-tale, and the spare damage will probably be allocated better. Sorry.