Stabbing pain in nipples while in the shower ?

Soo yesterday I had this incredibly painful sensation in my boobs yesterday while I was in the shower . I never had this before so it kind of scared me a little . I usually get just mild pain in them before my period , but this pain was way different .(I'm due 4 my period but It didn't come this month so far..) this pain felt like someone was stabbing me in the nipples while I was in the shower..so bad that I felt like I was about to cry , I couldn't even let the shower run on them it was so bad . So ladies , have u guys ever experienced anythinq like this and/or do u have any suggestions on wut this might be ? Is it serious enough to call my doc and ask her about it ? Cuz like I said I've never had this before . Plz and thank u . I've heard this can happen during pregnancy but as far as I know I'm not preggo..my period hasn't come yet tho but pretty sure I'm not..