10 weeks ago I was told that I have a contusion in my left knee. I still can't bend it or twist it. Is that normal?

Not normal. If you knee has not returned to normal functioning after 10 weeks you need to be evaluated by and orthopaedic surgeon. You may have an internal derangement, such as, a torn meniscus that is causing the continued problem. You probably will need an MRI to help to identify the cause of the lack of motion and pain with torque.