How many ultrasounds did you have during your whole pregnancy?

So I went to my ultrasound tech to ask for some papers of an ultrasound I had at 22 weeks, and I told her 'so this is the last ultrasound I had to do right?' and she was like 'oh no, this is just the beginning' so I'm confused because I already did one at 6w, 13w, an elective one at 17w and the last one I had was at 22w, how many ultrasounds did you have? Aren't they supposed to be only three? Thanks!