Who is the father nased on testing done????

[mardiel]

I had my regular period December 18,2006. I knew I'll be fertile and ovulating so had sex on Dec. 28 & 30th.
Did not have a period on January, so I think. Had some spotting on the 14th of Jan. , car accident on the 15th (spotting stops, bleeding the following day and that was it.Took both HPT and blood test that week but turns out to be negative. Feeling pregnant the whole month of January. NO menstruation, spotting or anything on February, decided to have a blood work again on February 16th which turns out to be positve blood  with a 67980 HCG level. Then on March 2nd I had an ultrasound saying that I am 5 weeks and six days pregnant. My OB-gyne scheduled me for a NT ultrasound but when I got there last Monday, April 23 the technician said she can't do it anymore because I'm already on my 15th week of pregnancy.
I'm really confused now, does this means that I got pregnant December and not January because of the absence of my period (I'm always regular) or did i get pregnant sometime in January which i doubt will be the case since i won't be able to determine my ovulating period.
I keep on counting and based on the ultrasound I should have had my period on the 8th of January for my baby to be 15 weeks.
Please help me, I need help in this matter because I'm really confused and yes there is a question of paternity in this matter cause I didn't have sex with the guy i mention i slept with last days of December on any day in January but with a different one.
HELP PLS.
Am I just wishful thinking the man I slept with is the father?

[Mrs06chris]

If the ultrasound is correct then you probably got pregnant the end of Jan. I'm 16 weeks tomorrow. My last period was Jan. 11th and I concieved around Jan. 25. All my ultrasounds have confirmed this. Good luck.

[jennifer1977]

Only a paternity test could prove one way or another, but that being said, I counted on a calendar from your Dec. period, and from what could have been your Jan. period and none of those calculations add up.  If you started your period on Dec. 18th, than you probably were fertile on the 28th throught the 31, and you probably Ovulated in there.  The spotting in January could have been implantation bleeding.  Bc of the car accident, you cant really say if it was a regular period or not.  I would trust the earlier US bc even though I think it is off, Your baby could be measuring smaller.  And everyone on here has said the earlier the US the more accurate.