A Close Friend Is Experiencing Muscle Aches, Low Blood Potassium,

A close friend is experiencing muscle aches, low blood potassium, vaginal redness, and a saliva pH of 5.5, no rashes, or fever. Muscle aches have persisted for last month and seem to be concentrated in back, thighs, and arms. no discoloration in urine or stool. Some joint pain in wrists and ankles. muscle pain usually more noticeable in the morning. Ideas? Potential Lyme disease?