A vaginal pregnancy scan is performed approximately 3 weeks after a positive pregnancy test. By then you will be 7 - 7 weeks pregnant, because the pregnancy start is calculated as 2 weeks before the oocyte retrieal.
The doctor is looking for heart action and number of fetuses. By measuring the fetus from head to tail, the age of the fetus can be calculated, thereby setting a date for the expected date of birth. .
If all is in order, you will be informed about what is next.
If it is easier for you to have the pregnancy scan done closer to your home, you are welcome to do so.