Had lump on knunckle of middle finger. Thought it was a wart and treated with freeze off. It blistered and turned white around the edges. It never developed a black center like it said it would if a wart. It looks like it was - a burn from the freeze. It looks like an open wound on top (but it is a light scab) circled by a white rim and on top of a red swollen lump that is very painful. Does anyone have a clue as to what it is?