What Causes Sharp Pain And Bruise In The Knee Radiating Towards Shin?

Several months ago I started experiencing pain on the inside of my knee. It was slightly sensitive to touch, like pressing a bruise. I had no swelling or discoloration and have continued exercising, running and biking. Periodically the pain would worsen, occasionally feeling pain down through my shin into my foot. Pain did not coincide with exercise it usually happened at any time. In the past 2 weeks the pain has worsened dramatically. It is now throughput my entire knee including the back. I get sharp pain that lasts a few seconds and have just about a constant aching feeling. The pain running down my shin into my foot is far more often. It wakes me up throughput the night. The sharp pain comes when I am just laying down. The pain is hard to describe. It is sharp, squeezing, stabbing in various parts of my knee. The pain in my shin and foot when it travels, feels like nerve pain. I did not injure myself before this started, I do not have any swelling or discoloration. My range of motion is not impacted. The pain is getting worse almost daily.