Looking for some hope

I'm currently 11DPO according to my app. Possible ovulation day was December 10th! Could it be possible ovulation happens like 12-48 hours after December 10th so maybe I could have ovulated December 11-12th? I'm still testing bfn and I'm starting to lose hope and thinking I have to start looking forward to testing opk next cycle! Anyone had a late positive? That's the only thing I am hoping for since my period isn't here. Just have a feeling it'll come out of nowhere. I'll get no signs and my period will just show up randomly!