this sould help to figure it out
First Day of Last Menstrual Period: March 12, 2010
Probable Date of Ovulation: March 26, 2010
Possible Dates of Conception: March 22 to March 30, 2010
Due Date: December 17, 2010 (40 weeks)
according to the calculator, it is your current mate.. but best way to tell is dna test
What if my last period was in feb. Is the ultrasound wrong on my due date?