Rash on scalp that turned into a bump and doesn't go away for over a year

[Leonie42]

In February last year I noticed i developed small light brown rash on my scalp near my headline and ear. For months i hasn't changed or disappeared, but now something resembling big pimple or bump grew on it this month. I tried to squeeze bump is still there. Bump is in the center of the rash that is still visible. Oh hurts only when I pull my hair or touch it. Hair stopped growing on the rash when I first noticed it. The rash is approximately 1 cm big. Do you know what this could be? I am 19 year old female with pale skin and no other diagnosed medical conditions.