I'm 37 and I am having a dark to black discharge in my panties, but when I wipe is clean and clear. But my panties smell and look  awful.  When I wash them they return clean then the same strain appears after I wear them again.  I had a full hysterectomy   vaginally and by abdomin 5 years ago,  it is so annoying and embarrassing  I am not sexually active just freaking out! !!!! HELP