What does low potassium and low glucose cause?

Depends on level: Low potassium can cause muscle pain, cramps, weakness, paralysis, and even heart rhythm disturbance. Low glucose can cause a variety of symptoms including shakiness, sweating, palpitation, and most concerning brain dysfunction, e.g. Confusion and even seizure. Above are not complete lists. Extent of symptoms are in part related to severity of drop in levels.