If you use diuretics they can lead to low potassium. There may also be an underlying medical condition. Your doctor is the best to advise you on this. Low potassium is just as serious as high potassium, as both can lead to heart arrhythmias, etc.
Sometimes there are no symptoms, can elevate blood pressure and provoke cardiac arrhythmias, muscle weakness and cramps. Severe lows can cause nerve paralysis and respiratory depression. You should see your doctor.