hi there. im really interested in hearing more about your symptoms. Sounds as though they are similar to my own. i have had a dull ache in my lower right leg for 5 years. It is worse at rest, and particularly when trying to get to sleep (it can and often wakes me in the night). Can only really sleep when i take a couple of over the counter painkillers. I cant place exactly where it is originating, as i can feel it in different areas - like you it is below my knee and above my ankle. Just that it feels as though it comes from deep in my leg. Interestingly if i elevate my leg, the leg starts to shake. It doesnt hurt when touched, or anything like that. I have hadMRIs on my leg and back, nerve and muscle studies, taken amitriptyline. Nothing has worked, or provided any clues.