I agree with Frank... I thought the ultrasound cone was more uncomfortable than the biopsy "sticks" from the gun.
I found that taking deep breaths to stay calm and not thinking about what my surgeon and the nurse were doing and seeing really helped.
They were very nice and asked me frequently if I was doing okay, which helped.
In the back of my mind, I counted down the "clicks" for each "stick" and said to myself "one less to go!"
Afterward, I asked for and drank 12-24 oz of liquids (7-up and water) before I left to exam room. That seemed to help a lot as well.
I know you'll do fine!
All the best,