Wow this is interesting - i would want to make a complaint as the sonographer would need to be made aware of their misdiagnosis, but i wouldn't want to cost them their job.
When i had my 2nd child i was told at 37 weeks, that he was breach, and i was given a date for an elective ceasarean, however, i knew that a few days later he turned, and it was the most amazing, weird feeling in the world. I phoned the hospital and told them so they re-examined me and told me that he was still breach. So the following week i had my ceaser and surprise surprise he was head first. They offered me the procedure to complain and seek professional advice, but i was just glad my baby boy was ok, and never took any advice or action.
I appreciate that what you were told was horrendous, and your gut feeling was to not take medication, and i'm really pleased that you are so far into your pg now.
All the very best.
xx