OK so I had sex with a guy more like a one night stand beginning of August. Got with my boyfriend now middle of September if I remember right I had my last period beginning of October... found out I was pregnant beginning of November... if I'm guessing right I would have conceived end of October if I'm due around July 12th correct? Just want to double make sure it couldn't possibly be Aug guy?? My boyfriend thinks I'm nuts but I've been through a lot and I worry a ton and expect the worst can someone reassure me please?

I'm sorry, but we cannot reassure you. The only option you have is to have a DNA test done once the baby is born.