If you conceived January 21, the doctor would tell you that your pregnancy began two weeks before that, or January 7th. That is when your last period would start, if your conception date was January 21, based on averages only. OK, if she is beginning the count on January 7, by today, you would only be 5 weeks 1 day pregnant, so whenever you got the ultrasound (presumably before February 9, since you had had one by the time you posted), you would not have even been more than 4 1/2 weeks pregnant counting the medical way. They say in the literature that nothing can be seen on an ultrasound at 4 weeks pregnant besides a slight thickening of the uterine wall. If you were closer to the end of your 4th week when you had the ultrasound, maybe more can be seen, but not much more than a fetal pole and maybe a flutter. So the doctor should have told you that it would be an imprecise measurement. Nothing can be said of a definite conception date as early as this.
If your choices of father are either your ex or 'somebody,' neither one sounds like a very good bet for being a present daddy in the child's life. I'd make plans to get an ultrasound at about 7 weeks (counted from the first day of your last period), and then also to get a DNA test once the baby is born. When the two candidates are that close together, you need a DNA test absolutely no matter what early ultrasounds say.
When did you have the ultrasound?
she did a measurement and from the ultrasound thats what she came up with, she said in a couple weeks when im further along she will be able to tell a little more
What year are you talking about? If you're talking about 2011, how could the doctor tell you that you conceived January 21? It would be too early to see anything on an ultrasound. Did he just tell you this by the timing of your last period? If so, there is no guarantee, it could be either guy.
If your doctor told you the approximate date it is probably the closest encounter to that date. However, since you did not use any form of birth control it really could be either guy. Be truthful with both guys and let them know you are unsure about the paternity and then as soon as the baby is born have a paternity test.
For future reference pulling out is NOT a form of birth control. Males pre-ejaculate and neither them or you would be able to feel it. Planned Parenthood offers birth control for super cheap.
Well more than likely you did conceive on the 18th, however only a paternity test will be completely accurate. Pregnancy is obviously more likely without a condom, but nothing is fool proof.