Hi SaraMc,
I usually get sensitive/sore nipples that "stick out" straight after i ovulate, though i have very irregular cycles so it can be hard to pinpoint exactly when i ovulate. It usually lasts about 5 days or so.
I am going through the same thing. I am 5dpo, Slightly sensitive nipples, but no sore boobs at all. However i have had cramping and pains in my lower back and last night i was sick like i was getting the flu with aches and pains. But today i am fine (other than having a bad sleep) It's so hard not to over analyse things when you are TTC!

It could have been that you had a really good "O". If they stay sore and sensitive by 10dpo i would do a HPT.

Good luck