Please take a look at my chart. I've been waiting for O to happen but I'm still not sure if I did.

FF put the crosshairs on this morning. Is it SAFE to assume that I have ovulated on Day 31 (5 days ago)? Or it is just FF's "guess" because I entered EWCM and cervix high/soft/open?

I'm CD 36 today and my breasts are a little tender. Is this a post-ovulation thing or most likely during? Or even before? How do I pinpoint my O-day if my chart doesn't exactly look biphasic yet? Also, what is the horizontal red line for? Is it an average?