So the first time her and I had sex was either the 29th or 30th of sept. Her due date is June 26th, and the weekend before she had sex with her ex. I don't know if it is mine or not. I look at all these calculators and all that, and all it asks me is the first day of her last period.. I don't know that, and I am completley stressing out. Yes I should have been more careful, but I just want to know if it is mine. When I put in the due date to certain calculators, it says that she has been pregnant for 93 days, and we had sex the first time 82 days ago.. I just don't know. Any help??

There is no way to tell for sure until you have a DNA test done.

An educated guess tells me that she conceived on or around October 5, but that is strictly a GUESS.

Having intercourse with you and the other man a week apart makes it impossible to tell who the father might be.

But if she conveived around oct 5th like you guess, wouldn't the due date be in July? That would be the full 9 month term right?

Pregnancy is a 40 week gestation. Conception on or around October 5 would give her a due date of June 26.

But there is no way to tell a date within a week, it is always a best guess or educated guess. So since they had sex within a week of each other, you will have to wait and get a DNA test

It is hard to guess or predict who the father is. Has she had sex with anyone since the first time she slept with you because although she slept with her ex the week before its looking more probable that it was too early for her to conceive with him as sperm doesn't live that long. I would say that a week gap between having sex with two people is far too close together to even have an educated guess.