Oh gosh, that's happened to me! But only once, and wouldn't you know it was right in the middle of a live performance?
Here I am, right in the middle of a complicated dance number my agent insists I do, when I bend to do a move and snap! It hurt unbelievably, it kept poking me all through the rest of it!
And of course, who thinks to bring a spare brassiere with them to the set? Not I, so I had to deal with it through three more wardrobe changes and another six songs. It was horrible!