I think that your methylation process kicked in more than in the past - that is why you've "suddenly" run out of potassium. Maybe because you've started to take something fermented upping your levels of B9/B12.
As for the supplementation, I encourage you to eat high quality DARK chocolate (lots of potassium bicarbonate) instead of the chloride form. If ingesting Sugar is not an option, you can always opt out for cacao nibs.