Dear Marijhd
Tiny (pianless not progressing in size an red sopts) can be DE MORGAN spots. You can see lots of pcs of de morgan sopts and compare it with yours.. But of course would be a Doctors openion.
Best wishes
Dr Tewari (India)
Dear marijhd, The skin on the breast is like skin on other area's of the body and subject to a variety of conditions. As this is worrying you it is best to bring to the attention of your doctor who can evaluate this in context of questioning and physical examination.