Suggest Treatment For Motion Limits With Stiffness In Knee After Injury

I hyperextended my right knee 6 weeks ago. It is healing, less pain, but I still have range of motion limits with the bending of the knee. Two days ago my right heel went numb (as if "asleep") then my right big toe. There is occasional aching in the right buttock and ham string area. No real pain. One week ago I resumed a strenuous exercise routine, as well as speed walking. Are these all related? I am female, age 55, 5' 3" 128 lbs. and exercise regularly and am very active.