I've gotten ingrown hairs the size of those giant marbles you use to shoot at the smaller marbles. This is a really awkward comparison, but if you know the ones I mean, you get what I'm saying. They're a bit smaller than a superball.
In other words, yes, that could definitely be what you're feeling. Mine tend to be very painful, at least until they pop, but I don't know if that's a universal thing.