Burning nipple sensation

I'm on CD 14 (maybe give or take a day or two, I haven't been keeping track) and all of the sudden my breasts feel like they are ON FIRE today.
 It started this morning and I decided not to wear a bra to try and help, which ended up being the worst mistake I've ever made. I can't stand to have anything touch them, they hurt so badly! I'm looking back at the last few days and noticing odd symptoms as well, mild nausea, crying at the most ridiculous things, a small bit of bleeding a few days after ovulation... something is not right.
The biggest thing is, I have a copper IUD! I shouldn't be able to get pregnant but here I am worrying about pregnancy.
Anyway, did any of you feel this insane burning in your nipples early on in pregnancy? What about IUDs, has anyone gotten pregnant with an IUD? Or noticed nipple burning sensation with an IUD in? 
I'm taking a test tomorrow morning and I think I'll go ahead and make an appointment with my doc to see what's up. Just hoping from some insight from you all!