ACV is a queer substance in the body. If you happen to be over alkaline, it will help to ensure that the calcium stays or goes into solution to keep it from collecting in the body and causing problems. If you happen to be acidic, ACV will help to activate any calcium that is ingested allowing it to taken up and used by the body. However, the key is that when you are acidic you must have adequate calcium for the ACV to activate. In the absence of adequate calcium, the ACV continues to have more acidic effects in the body. In my case, ACV dries me out without calcium.
As for lemons, keep in mind that lemons contain quite a bit of vitamin C, and if you are suffering from a deficiency of any mineral that is antagonized by C, then that mineral will only be further depleted.
In this situation, potassium may or may not have been involved with your reaction, but I definitely believe that the ACV and lemon were not helpful in this situation.