Almost certainly
sebaceousBirthmarks - pigmented
Hair follicle sebaceous gland
Sebaceous cyst cysts (similar to blackheads); when they become infected, it is called folliculitis (the larger red bump). Not an STD. This is basically a version of
normalNormal saline flush anatomy, although in some cases the problem is promiment enough that treatment (e.g., low-dose antibiotics as for acne) may be warranted. See a health care provider for confirmation and further advice, but in the meantime don't worry about this medically minor problem.
Best wishes-- HHH, MD