A few weeks ago I noticed a black spot on the bottom of my foot . Tonight, I looked at my foot, forgetting all about that spot and I ve noticed it s grown at least double in size. It does not hurt. I have not been walking around outside without shoes on, so stepping on something wasn t the initial cause...I m a 25 year old Caucasian, female. Do you have any idea what this could be? Should I wait to see a doctor and just monitor it for a while? If yes, how long should I wait?