Can you please answer few of my queries related to your question,
1) Do you have any history of lower back pain
2) Is your knee get stuck when you walk , or feeling of something popping out ?
3) Are you into any activities/ Hobbies ( Like running, gardening etc) ?
4) You stated you had done every test possible , Is your level of Calcium , Sodium, Pottasium under normal level ?
5)Which part of the day you get these symptoms very worse ?
6) How you feel during weekends ?
Please try these , add calcium supplement
tabs, Mix little bit salt in a glass of water and drink and mild or gentle stretches to your calf muscle and hamstrings. If you had done any of these above please tell what was the effect of it ??