So, if I'm regular, like every 27-28 days when should I ovulate? I've tried opk and always negative so I think im missing the ovulation window each month. Hubby and I have tried for 3 months and nothing, dr said since im regular I shouldn't have anything preventing me from ovulating. I started my period last wed day 9/24 and still on lightly. Hoping to be done by this Tuesday. I have 6 apps with all different fertile windows. HELP