What Causes Swelling,itching And Sores On Feet?

Yesterday i woke up with swollen and hot to the touch feet that hurt badly. I can hardly walk on them. Today they are worse. They both hurt more and are more itchy. I soaked them in epsom salt and it looks to me that sores are appearing. I did not step on any thing different or burn my feet or anything. I have no idea what this is. Can some one please helo me? I went to the doctor and he could not figure it out either. THe pain and itching is almost unbarable. Any thought any one please???????