What I'm talking about is what happens when you try to pop a regular old zit and it pops the wrong way into
your skin. It doesn't start off that way, it gets that way cause you mess with it. Seriously, like you get one in the crease of your nose, by the nostril, that can swell your eye above it halfway shut. I don't and never did have anything like the people on proactiv commercials or anything, I never needed a prescription, etc, I just had regular old teenager skin that got zits during, ahem, a certain week of the month, and this happened to me three times! You'd think I'd have learned after the first one.
If you squish them it's also more likely to scar.
My favorite thing to use for the occasional one from exams or whatever is that little tube of Clean & Clear that is clear gel with salicylic acid that you just dab on it, I swear its like a miracle thing! Like, a spot treatment thing, I'm sure other brands have similar ones.
Didn't mean to scare anyone!