I had my period January 10th. It lasted 5 days. My period ALWAYS comes the 10th of each month and lasts 5 days. January 17th I had sex with my ex unprotected. My husband and I got back together shortly after. I never got my February period but my doc says that by ultrasound I conceived around February 12th making my baby due October 30th. Making my husband the father. How accurate is this?!