26 years, 164 cm (5 feet 4 inches), 50kg (110lb)

14 days ago a whitehead pimple (only the white cap of the pimple, no red, no swealing) appeared on my birthmark (I had this birthmark for the whole life, it is on my face it is about 1,5mm in diameter, slightly elevated and light brown colour). The pimple cap appeared in one day and did not change it's shape since, it does not dry up. On the surface of the mark around the cap some veins can be seen which usually were not (can this be due to mild inflammation caused by the cap?). It does not itch or anything.

I am a bit concerned though since it is persistent, should I show this to my doctor/dermatologist?

How long is it "safe" to wait for this pimple to go away on it's own? How long does a whitehead usually heal?

I thank you for your answers.