Brown Discharge

Hey ladies! I'm on month 8 of ttc. Cycle day 15. I woke up and have wiped brown discharge. It's not a ton but it's not a spot either. This has never happened before. I should be ovulating right now but I have never had discharge with ovulation. I've not been taking ovulation tests, I just go with when the <a href="https://play.google.com/store/apps/details?id=com.glow.android">Glow app</a> tells me I should be ovulating. Im wondering if I ovulate earlier than I thought? Any thoughts?