Susan, I think you've considered this situation very thoroughly and I don't see how anyone could possibly add anything to it that would be enlightening.
I dont know about your situation, but i can tell you my experience. When you dont know the exact day of your last period, its really hard for them to see how far along exactly you are.
My last period was on April 21st. I went for my first ultrasound when i was suppoused to be 10 weeks. they told me i was 6 weeks not 10. That confused me because i missed my period in May and now they count it as if i had it. Then when i was 21 weeks, (counting as it said on the ultrasound the first time) they told me it looks like i was 18 weeks not 21. which didnt make sense, because then the first time i would've been 3 weeks pregnant which they wouldnt see anything, there's no way they could mistake that for 6 weeks, so i keep counting as if i was 6 weeks the first time. Now whenever i go they say some different week i am in, and its never the one i keep counting as. Different babies develop differently and they can be one or two weeks off, thats what the doctor told me.
Hey.. i am a hundred percent sure of all my dates and everything and I've only slept with my husband on a specific date and my baby is still 8 days older than expected.. so a week's difference in dates is not that big of an issue.. the dad could be the 17th guy in your case, your baby just grew faster like mine..
Paternity test is of course the answer. At the end of it all you don't want to have the wrong person raising your child but the guy on the 17th sounds like the more accurate choice because he was the one of the two that did ejaculate in you. Good luck and best wishes. God bless
I'm facing a similar situation, I had my lmp on the 3rd August I had sex with my bf the 9,10,16 and 17th August, in September I had no sex but my period was on the 10th or the 12th September and it was light and lasted for two days,I then had unprotected sex with my ex on the 3rd October and I took the emergency pill,I discovered I'm pregnant late October and went for a scan on 5th November and based on measurements of the womb it was saying I'm either 6 or 8weeks pregnant,but the Dr claims I got pregnant mid august but aren't my weeks supposed to be more?
My due date doesn't match up either. I never had sex anywhere near my date of conception. Also I had already gotten a positive pregnancy test by my "date of conception" my baby measures 3 weeks ahead which would go with when I was sexually active. Even my doctor Thinks my due date is off but they won't change it.
If you have unprotected sex, the guy doesn't not have to finish for you to get pregnant. Pre-ejaculate contains sperm and can cause you to get pregnant. You will need a paternity test to know for sure.