What Is The Treatment For Swollen Painful Heels?

I have really bad pains in the back of my heels they are constant anymore. There are times they will be sharp like a knife stabbing into them. They are swollen and deformed looking and causing me to walk with a limp. They feel warm to the touch and I am not able to do what I used to be able to, can you help and tell me what it may be and what I need to do.