I’m curious (and nervous) about what it means when I comb out two scalp hairs that both stem from a single, hard substance that looks like a follicle. My hair is too short for this to be a split end. Is it a follicle these hairs are attached to? If so, why are there two hairs growing out of it?

Hair grows from a follicular unit in one, two, three, or four hair groups. It seems you pulled a follicular unit that had two hairs.