Knee swelling and pain since two months increasing upon activity no releif with antiinflamatory xray shows no bone deformity?

MRI. Knee pain and swelling can be from a variety of problems. Inflammatory issues such as arthritis, synovitis, tendinitis etc. Can cause pain and swelling. Injuries such as cartilage or ligament tears can also cause pain and swelling. See your doctor and request an MRI as these are all treated differently.
See below. It sounds like you need an aspiration with studies performed on the knee fluid and a MRI at this point to better determine what is going on.