Talk to Orthopedic on Back Bone, Back Side Of Neck, And Knees Pain

I got my Vit.D levels checked almost a year ago. which at that time was 4. I had pain in my back bone that used to occur occasionally whenever there was some workload or some academic pressure or physical exertion. I continued taking osnate D tabs with indrop d injections for really a long time after certain time intervals as directed by physician. but now the pain has even got worst and now I am suffering from severe pain on the back side of my neck and even my knees hurt so badly along with back pain when I don't change my posture for quite a while. my body don't tolerate one position for more than I guess 10 mins. I have to change my posture i-e if standing I have to sit or if already in sitting position I have to lay down for a while to fully extend my legs and neck for a while. kindly guide me about the reasons for these and an appropriate solution for it as well.