How likly is it that I conceved befour my period.!

Patient: I had sex with anpther guy the day befour my period on june 25th and then was back with my boy friend on th29th the day I ended and the doctors and altrasound teck said l conceved on the 10th of july how likly is it that it could be the other guys kid. Pleas he me answer this thank you

Doctor: