8 weeks, 4 days upcoming sonogram help

I had my initial Drs apt today. Mostly blood work and medical history. I received a referral to get an ultrasound done to figure out if everything matches with my last period. According to my period, I am 8 weeks, 2 days today. My apt is now scheduled for this Friday, so I'll be 8 weeks, 4 days. They said to drink 16oz of water an hour before my sonogram. Does this mean I will have a transvaginal or transabdominal sonogram? And should they be able to see the baby and hear the heartbeat?? Will I get my due date at the sonogram apt? Or will I have to wait until my 12 week apt (Oct 14) to find out my due date?