TMI - sore, erect nipples

I'm 12 dpo and the last couple days my nipples are been almost constantly erect as sore.  I always get breast tenderness between ovulation and AF but I've never had nipple symptoms before.  This is our third cycle TTC#1.  I managed to psych myself out last month so I'm trying not to read too much into my symptoms.  I've read nipple symptoms are a common sign of early pregnancy.  I know the only way for me to be sure is to wait until I miss my period and then test.  Has anyone else experienced this?