I have had these black-purple bumps on my stomach for years now. they do not itch . They are just under the skin , you cannot squeeze them until the end of what i like to call their cycle. When that happens, if i do squeeze them, a sac/ seed like gray/white substance with a black tip comes out, the spot then becomes a hole and it gets inflamed. Help please, i do not know what these are i have tried going to doctors heard different things but none have helped. They are all over my stomach/abdominal region; recently some on my back.