I Have Tendonitis In My Right Ankle So Have Been

I have tendonitis in my right ankle so have been leaning more on my left leg. I am told I need a knee replacement on the left and have been having pain. Suddenly, I got an electric shock type pain in my shin that was very severe and now I can barely walk at all with a walker. I get this if I turn a certain way or lift my leg. What could it be? Thanks,

Susan