If my transvaginal ultrasound said i was 6 weeks 3 days on june 11, 2012 when did i conceive? is it possible i conceived from an april 29 encounter?

Unlikely: According to a pregnancy calculator, your most likely date of conception would be around may 12th. Now, having said that, all women ovulate at different times of the month. Women have been shown to ovulate when they are still menstruating, for instance, day 4 of their cycle. April 29th is off by nearly 2 weeks, so i would guess conception was a little later. Hope that helps!