A Wart-Like Growth That Came and Went

Approximately 2-3 months ago I discover a very small growth on my scalp.  This growth first appeared to be a typical small skin colored mole.  Over time however, it grew quickly and then become what appeared to be a wart-like growth that was not symetrical and became lumpy, very similar to caldaflower. It grew to about the size of a pea, didn't bleed but would get dry and crusty and some dried tissue was come of from time to time.  I completely left it alone and didn't pick at it or disturb it in any way and then about one week ago, I noticed that it started to shrink in size and eventually, it just dissappeared, leaving no scar or any noticable mark.  

CJChryst