Ovulating or Pregnant? So confused!

Kristal

So...I'm 1-1/2 weeks late for my period (I was due on 8/23) and my cycles are typically 30 days. I had all the symptoms (sans morning sickness) but all my pregnancy tests have been BFNs. I decided to take a OPK just for the heck of it and got a steady smiley face which is supposedly "peak fertility". Is it possible I ovulated late and that's why I haven't gotten my period yet? I had sex with pre-seed just in case but I'm just baffled.