Severe knee pain making my back stooped.

As per knee x-ray 1.osteoarthritic changes spotted with small marginal osteophytes. 2.soft suprapatellar tissue swelling noted. 3.the knee gap has been increased. there is a visibly big swelling on my right knee and the lower and side part of the knee has got a bulge too.it is causing extreme pain.at present,i am consulting a doctor and taking medicines prescribed by him but it is of no use the doctor told,there's a lump in my knee.i wear a full length knee guard and i have done 14 days Ultrasound therapy and i regularly do exercise as prescribed by him still i can't walk normally and can't sleep at night due to excessive pain at night.sometimes my knee and the thigh part become so stiff that i can't lift them or move them.i scream due to pain.it has been six months ,i am taking medicines and still i can't walk or do household work for 5 minutes at a stretch.i have to walk or move with the help of my family members. in fact,it is spreading from knee to thigh,waist and the whole leg.