I had a mirena removed at the end of June going into July than I had heavy bleeding a couple of days after that but the month of August I didn't have a lmp or the begging of September I didn't how will I know when I ovalated but me in my boyfriend had sex August 20 in September 16 in 17 when I went to the doctor I was 9 weeks in 3 days on November 11 in my due date was June 12 so which day did I most likely conceive on sense both August in September I skipped my lmp from the mirena

So, on Nov 11 you were 9 weeks 3 days along? How did You determine This? Was it based on measurements from an ultrasound? Or was it a rough estimate provided by the doc?

Also, you had sex August 20, and September 16 and 17? So you are trying to determine which of these days is the conception date? There is really no way to tell when you conceived, even if you knew your LMP.

Is there a reason you need to know the conception day? Is there a question of paternity?

Nall the doctor told me by ultrasound how far long I was in she said that I got pregnnat in September in that August has nothing to do wit my pregnancy

She is most likely correct then. There is almost a month difference between the August and September dates, which would show up in the measurements via ultrasound as a significant size difference.

So if I would have got pregnant in August when I found out I would have been most likely 13 to 14 weeks

If baby measured around 9 weeks on November 11, and you have a due date of June 12, you would have gotten pregnant in September. Ultrasound can be off a bit, especially towards the end of a pregnancy, but early on it is fairly accurate for dating a pregnancy. There is a big difference between the development/measurements of a baby at 9 weeks gestation and one at 13 weeks gestation.

The lack of a period for August was likely due to having recently come off the IUD. It can sometimes take a couple of months for your body to adjust to the change in hormone levels. You wouldn't have had another period after that since ovulation occurs first in a cycle and by the due date for the next period, you were already pregnant.