My Left Foot Has Started To Hurt So Much. I

My left foot has started to hurt so much. I thought I had just worn my boots too long, but the pain is pretty severe and feels like it's radiating up into my calf. There is no redness or swelling. But everytime I stand up to walk on it, I am surprised at the amount of pain. Dull/achy pain...nothing sharp, but I've never experienced it before. this is the third day of the pain. I can walk fine on it, but it doesn't feel very good.