Burning sensation in my legs at night?

For years I have had burning hot feet at night( since I was a child), I have Always kept my feet out of the bed covers to sleep at night. Over the last year i started to get burning legs once or twice a month. Now I wake up every night after an hour or two sleep with my legs on fire, I have to sleep with just a sheet on me from my waist down to my feet but have to have a cover over my top half as this is just normal temperature.I don't even feel tired with the lack of sleep, its like my mind is buzzing and wide awake during the night. I often get up from 2-6pm and watch tv or clean the house, then go back to bed for 2 hours at 6, my legs don't seem to burn at this time in the morning just in the night. I thought it was the menopause as i am 47 but doctor did blood tests and said that is not the case. She doesn't know what the problem can be.I also suffer from cold feet in the daytime. Does anyone have any sensible suggestions please.