What should i expect during my first ultrasound today?

I am going to have my first ultrasound today at 5pm i have been counting down the days. I am 9 wks and 2 days. But i have a large uterus so they think I am future along or something is up like a cyst or multiples. I just cant wait to see the baby. And are they going to do a vaginal one because my mom , dad, and fiance want to be there. I rather them do the one over my tummy. Also what should i expect at 9 wks.