AF finally came at CD38 :(

E

I'm very sad because I'm not sure what we're doing wrong. I looked at the calendar and due to AF coming CD 38 then that would mean 2 weeks ago on CD25 I must have ovulated right? If so we bd on Cd23 and 24 so if I ovulated on cd25 shouldn't I have conceived? I'm very freaked out about this. I don't know what we should do differently next time. Any advice would be appreciated. Tia