This might be a reaction of the skin due to a fungal (yeast) or bacterial infection (particularly, an infected hair follicle, or folliculitis), though itching would likely be accompanied. Chanchroids are lumps that form on the genitalia from a bacterial infection, and bumps can form from contracting syphillis and herpes as well. These generally appear as blisters or ulcers that eventually crust over and heal over a period of a couple of weeks. Herpes tends to itch and be painful, whereas a painless ulcerated lesion is more typical of syphilis. A visual examination or cervical swab, bump swab, and/or blood tests are needed to determine the exact cause of your symptoms, since the treatment depends on the nature of the cause.
I hope this helps!