Clomid question!

Hey all- I started my period today and am supposed to start taking Clomid 100 mg tonight. I called my dr when I started bleeding like he said and I booked my appt. for an ultrasound for next Thursday which will be CD 10. The receptionist I spoke with was very impatient and in a rush to get off the phone and told me the date/time of my appt. and basically hung up. I had NO clue that saline ultrasounds were part of the monitoring and had no time to ask, I just thought it was a regular us? I will def call my dr's nurse tomorrow to clarify but any other ladies have any knowledge to this? This is my first cycle starting it. I had a saline us last Nov. and 😩😱 was it painful. Thanks girls😊