What Causes Knee Pain After An Injury?

I'm having knee pain on the right side of my left knee, the pain comes and goes,and also hurts when I rub it with a little pressure.Sometimes when i sit down there is a pinching feeling above my knee in which I cannot move, I just sit in pain. I had an injury from sports about 9 months ago that involved a bruised bone, a possible meniscus tear,and and strained ligaments. After practice I ice it, but it seems to hurt more after I ice it. Should I see my doctor, or just go through the pain?