 [ Symptoms ] when did i most likey have sex to become pregnant  i got my period on august 1st i was expecting my period september 1st but it did not come i took a pregnancy test today the 10th the test was positive and it said i might be 2 and up to 3 weeks since ovulation it also said my doctor would date me at 4 5 weeks pregnant i am just really confused by all of this and i would like an estimation on what day i had sex to become pregnant thank you [ Disease ] according to a reliable pregnancy calculator and based upon the 1st day of your last period the following information is revealed estimated due date is 5<negative_smiley>2015 gestational age today 9132014 is 6 weeks 1 days or 1 41 months months date of conception was <negative_smiley>152014 i hope that this answer has been helpful