What Causes Tingling Sensation Below The Knees?

Hi, when I start to lie down at night I get this tingling right below both my knees in the front calf area. Then within a few seconds a pain that is unreal.. Even my pain meds will not stop it.. I have walked the floor as high as 4 hours before it stops.. Do you have any ideal what is going on and what I can do to relieve the pain??