3 days before ovulation

TTC is way harder than I ever thought ! Hubby has a low sex drive and I have 35 day cycles. I've been trying to BD once a week until I knew for sure when I Od. Well, I got my first positive opk yesterday and i was so happy I cried!! (i was worried i may have PCOS). Anyway, as much as we tried, BDing was not happening last night. We did  BD on Sunday...three days before ovulation. Do you think it's still possible?? I would love to hear anyone's success stories. I'm hoping we can try again tonight but it might be too late.