Do you ovulate at the same time every month??

So, I’ve been using ovulation strips the past four cycles, I am also nine months postpartum, my period now has regulated after I stopped breastfeeding at five months. The last two cycles, I’ve gotten a surge at CD15, is it safe to say, my period and ovulation are now back to normal, my cycles have gone back to 27 or 28 days. Should I be BD today and tomorrow?? We didn’t yesterday and I’m afraid we missed our chance. The last time we did the deed was 2 days ago, I’m planning for today as well. This is today’s positive test result, I realize some of the other tests from CD 12 are not fully dry but sometimes, if I don’t see a clear line, I know it’s negative.

Vote below to see results!