I was thinking boil, but it's mobile and hormonal must be a teenager. It's been popping up in 2/3 different places along the back of my neck over the last year, always a couple of days before my period hits. It's defined and solid, tight, itchy and painful but never comes to a head. Instead it lurks like an evil eye for about a week then skulks back to pop up in another 4 weeks. I exfoliate when I think of it regularly but the only thing that seems to have any impact is pixie glow tonic - glycolic acid?
Obligatory photo attached. Now on day 4 so it's receding (and I'm a little tipsy so not sure if the poor focus is me or the camera 
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