It could be a boy. Or it could be a girl. The heart rate theory has yet to have any true significance. Both my boys were in the 160s. It means absolutely nothing. Also, the baby measures big or you measure big? If you measure big, that is likely because it is your 2nd baby. Everything is stretched out. If the baby is measuring big, it could be because sonogram measurements are not meant to be accurate to the day. You are certainly within a normal range. In fact, by the end of pregnancy, the weight measurements can be off by 2 pounds either way! They are doing the best they can with the image they have, but it is not 100% accurate like if you were to see the baby in person. Neither of those reasons means or even suggests that you are having a boy. As far as your pregnancy symptoms go, you can have very different syptoms with the same gender or very similar experiences with different genders. And you aren't out of the woods on the morning sickness yet. I didn't get sick until 7-9 weeks with my pregnancies! I would prepare yourself to have a boy, but not because of any of those things. Guess what? You have about a 50/50 chance of having a boy! Dont' worry and go on enjoying your pregnancy!