I have noticed several black spots on the shaft of my penis between the head and crotch area. This started yesterday and they measured about 1-2 mm in size. Now they are about twice the size and there are many more and they are a purple color now, like a bruise. They are starting to itch , as well. I haven't had sex for months, but do masturbate occasionally. I was diagnosed with balanitis 2 weeks ago, but that has cleared up and I shower more frequently now. I have a photo if I can get it to upload here.