I get to the boss and die after getting 50-75% of the way through the battle a few times. Then my game starts lagging a lot to the point that half of everything doesn't recognize I'm hitting it (also my pc is not a potato). Also, flamethrower ammo and health drops are non existent in the boss phase, is this supposed to happen?  Lastly, coin counter decreases with every phase of boss battle, it starts at something like -1200 and does down with each phase (about -100 per phase I think).