Isn't that an awesome thing to see and hear!! I loved having all of the ultrasounds that I had because I got to see the baby a LOT when I was pregnant. When I found out that I was pregnant at 9 weeks, the arms and legs were just becoming formed and he looked like a little peanut and I bawled knowing that my doctor wanted me to give the baby up (not have him). I agree with Mel about just wait until you can see everything! I remember the day that I saw Brady sucking his thumb in the womb because it was on my Mom's birthday. It was soooo precious and I even got a pic of it.
Anyway....I hope that things continue to go well for you and good luck!