If you're 8 weeks post partum and you're not breastfeeding, it can still take up to 3 months to get a period. Ovulation is so sporadic after childbirth it may also be that you did conceive but aren't far enough along yet to get a positive, as it doesn't look positive to me. That being said, you're extremely fertile immediately after childbirth. I was originally planning to give my body 6 months to a year to heal before getting pregnant again after having my first but I shockingly became pregnant with my second only 3-4 months later... and I was on BC!