well according to the conception calculator...
First Day of Last Menstrual Period: June 13, 2010
Probable Date of Ovulation: June 27, 2010
Possible Dates of Conception: June 23 to July 1, 2010
Due Date: March 20, 2011 (40 weeks)
Based on the gestational age from the ultrasound and your last period, I'd say it's your boyfriend's baby, and you have a period between the two. Early ultrasounds can be off, but not more than a week or so. And the dates match up for it to be your boyfriend's baby.
According to your dates and the measurements of the baby, I would say that the father would be the guy in June. Good luck hun! H&H 9 months!
Im thinking the boyfriend