OB appts

This is my first pregnancy and I didn't get a very straight answer at my first OB appt today (I'm 8 weeks). I have my first ultrasound next week - is that an internal or an external? The receptionist told me both and then she said they have me drink something. 
1. What should I expect at this first ultrasound?
2. What should I expect from my monthly appointments? 
Thanks for your help!