TTC #1

Jess
Hi I'm Jess 25 from New Zealand, we are TTC with #1 but I'm confused and hoping for some helpful advice I have been on the OCP since I was 16 (so 9 years wow) but I don't know anything about my cycle. The last 6 days I've had very sore/sensitive nipples any ideas on why or what may cause this. TIA