When did I conceive

Hey guys!

So I have a due date of 9-3 going by my last period (which was a guess because they're never regular and I don't keep track of them)

I am trying to pin point when I conceived.

I can't remember the exact dates we DTD. ( he's out of town a lot for work) I can say Halloween night for sure.. and then a few times in November and then December. But once you've been with someone so long you don't really keep track of things like that. I'm not sure how accurate these online pregnancy things are. So any input from you ladies would be nice 👍🏽