First off, game's fantastic, thank you. Noticed an issue where my blood echoes weren't retrievable after death. I think it might have happened after the first time I retrieved echoes off an enemy? I tried killing all the enemies in the area but they were definitely gone.

I'm investigating this cause I'm also experiencing it and I think it has to do with loading screens? Try dying in the same area as the lantern you respawn from (if it's the Central Yarnham lantern there are enemies at the bottom of the ladder), and see if that makes a difference.