I Was Stung By A Bee 3 Days Ago On

I was stung by a bee 3 days ago on the bottom of my foot. It is so swollen up to my ankle bone, hard, and itchy. If I itch it burns. If pressure is applied it burns. It is turning a deep red color now. Why is this and what do I do. I have applied ice, a baking soda paste and soaked in very hot sea salt water.