Thanks for your query.
Well, you are in a very confusing state !
From the sonography
reports, it appears as if the baby was conceived around the 26th of October.
But this is highly improbably, as you mention that you had your period after just 3 days ( 29th october )
ALso, if the baby was conceived due to intercourse on November 10th, then it just cannot be 7 wk 3 d by December 17.
So it appears that you did conceive in October itself.
Please be sure that the dating of ultrasound
is exact, and by transvaginal sonography.
Also, for being 110 % sure of the paternity, you can only go for a DNA test of the baby, rest will always be assumption.