Thank you for your replies! I was working out doing Zumba which most likely brought this on, I think I twisted my knee in some way. The knee has not gave out or locked and there is no real pain when going up and down the stairs. It just perhaps feels tighter and clicks more. The main symptom is general weakness and like it could dislocate at any moment, not nice. If it is an injury related to the Meniscus or Medial ligament, do you know any treatment for it. Exercise strenthening the knee maybe?