Suggest Cure For A Painful Spot Appearing On The Calf

i have a very painful red mark on the inside of my calf. it started like an itchy spot but is more painful now , it has been there for two weeks now and is just getting worse, i have noticed i have one at the very botttom of my back now very sore red and leeking clear fluid, about the size of a ten pence piece, what could these b?