Suggest Treatment For Cramps In The Legs

Over the past 2 months I have been experiencing loss of power in both legs, in which one leg may come from under me. I also have crapms at the back of each leg which occur sometimes. I would also say that I am tired but I put that down to the fact that I work extremely hard. My GP has ordered fasting bloods for me and possibily a neurology consult if the bloods come back negative. Have you any ideas about this. I am a 37 year old female, not overweight, and overall have been in good health. thanks