Well, that's interesting the time of having sex without condom until right before ejaculation and having an ultrasound hours later. lol. But in general, while you can get pregnant any time you have unprotected sex as the penis emits small amounts of sperm at all times when engaged in intercourse . . . is it enough to get you pregnant since he put on a condom at the end? Possibly but very doubtful at this point. That coupled with your age. Women do get pregnant at 43 naturally. But I wouldn't be overly worried to be honest. Would it be awful to get pregnant just in case?