The Nervous Thread

My flatmate's friend had just got her nipple pierced and was taking a shower. She noticed there seemed to be a bit of thread poking out from said piercing. Instead of, you know, maybe trying to brush it off first, she took matters into her own hands. However, what she hadn't realised was that the thread wasn't a piece of thread after all. It was in fact a nerve. That for some reason during the piercing process had popped out. Still not exactly sure how but as you can imagine, scissors and nerves don't tend to make a mess. Ended up blacking out on the shower due to the pain. So many questions here. How is it not hurting