I'm Due June 14 So About When Did I Conceive?

These are too close to completely determine whose it is. I would just get thru and then deal with who the daddy is.  You conceived 40 weeks prior to your due date of that year.

There's really no way for you to know which one is the father.  You should have been most fertile between Sept 16th and Sept 21st.  Your actual ovulation day should have been the 20th.  The problem here is that sperm can live up to three days, so having sex on the 18th means you could still have had sperm in you when you ovulated on the 20th...meaning they could have met the egg.  The egg also lives for 24-36 hours.  So, even if you had sex the day after you ovulated, there is still a very high risk for pregnancy.  This is all assuming you have a typical 28 day cycle.  If it's normally shorter or longer, let me know, because that can change things.  Good luck to you.  I know things are hard, but that little baby will be worth it in the end.  :)

Stay safe and don't forget the condoms.  :)