Sore Nipples.

My husband and i are ttc baby #1. This is our first month trying after stopping the pill. Ive been off the pill for 3 weeks and i am so anxious to be pregnant. I had a withdrawl bleed 5 days after stopping the pill and then nothing since then. today my nipples are very sore and ive been getting headaches for a few days. Could this be from stopping the pill, ovulation, pregnancy, or a symptom of any of them? Thanks.