Nipples hurt SO bad

Ellie
Hey gals, question for ya...
My nipples have been hurting like crazy all day. I don't mean they are sore, I mean they HURT. Everything looks normal, they've just been hard all day and I've been in a lot of pain. No chance I'm pregnant, I just ended my period 3 days ago and haven't seen my boyfriend in 2 weeks because we're long distance. Any ideas??