What Does A Painful Brown Spot On The Ankle Indicate?

Have a dark brow n spot on ankle. Slightly concave. Had for years. Recently started hurting more of a burning feel which it has never done before. Dr told me that a lot of the brown dis coloring from getting ankle sprang was billieruben and may never go away which it hasn t, it s been yrs now since I injured ankle. I noticed there was a little drainage tonight on my sock. Have soaked in Epsom salts a couple times and when I get up in night and the blood hits the ankle it really burns. In morning it doesn t look to bad by night it s pretty red and looks like it could be infected but don t think it is. My mom has a similar spot on her ankle that drains a lot. I m active for age and get regular exercise, mostly walking and still play softball in summer.