Maria, my MW has told me that if you don't get an early dating scan, and if there is no medical reason for another scan, the 20 week scan is all you get.
If there were any issues or the baby's position indeterminable later on, then they would do an assessment scan. But if you are healthy then no scans!
OH and I would like to do a maternity shoot together at the hot springs near our place. Just don't feel like my bump is quite big enough yet