If your EDD is 12/14/12 then you add three months and minus 7 days....so 3/7 when your last mentral period was.... so let's see here. You had two light periods and a negative pregnancy test TWO and a HALF weeks after your first "missed" period. I think it's highly unlikely the baby belongs to the EX. Ultrasounds are not always right on the dot. Give or take a few days. Same with fundal height. It can be a lil off here and here. But your fundal height would be much greater especially since it appears it was weeks between the ex and bf? When were you with the bf after the ex? It takes ten days for the egg to "implant" and for you to be "officially" pregnant. It takes ten days to travel it's journey up the tube and make it's final home in the uterus then about a week for your homones to be at the levels for the preg test to show. You were within the time frame for it to appear on the test. So, does the bf know about this close call? He should be understanding. Maybe to ease both your fears you could do a simple paternity test. It's an at home kit you can have sent off. 100 dollars. Or one done in a lab for 300-500 and it's court approved. I think it's worth the money for the peace of mind. But I need a little more info on the boyfriend before I can be more of a help.
- I am a nurse.