Ok so I have been reading that some have missed their period for month of February...... Me included. I'm 10 days late and BFN. I run a normal 28 day cycle. Maybe stress caused my missed period and I see gynos tell a missed period occasionally is normal. So my question.....when do I start using opk again? From when I thought my period was going to be? All month of march? Or just go to gyno? I was going to wait til two week missed mark and then make appt. But I don't want to miss my surge this month! Thanks:)