Throbbing pain from behind kneecap running into bottom of foot. Hurts to elevate & rest. Foot gets cold then feels hot and tingly. Swollen more active?

Possible Baker's. Baker's cyst. Follow up with an orthopod that can evaluate you for this. Usually happens in the back of the knee, and presses on nerves and arteries which cause pain and burning sensation to the foot. Definitely get it check out.