TBH its sometimes just the way people say things rather than what they say.
For you, your scan is an exciting, worrying, once in a lifetime experience.
You've got X number of questions you want to ask.
For the sonographer ,you are one in a line of dozens of women having their scans.
They want to do the scan, then answer questions. They can't give you a full answer until they've done all the measurements.Sometimes they can't answer and they have to get the doctor in.
(I work in healthcare ,but not in maternity,and I'm aware how I say something can affect how the patient percieves the whole treatment)
When I had DC2, the sonographer muttered about 'low lying placenta', and my mind was "why,when,how, will I need a CS.I can't have a CS,I've got a toddler, I'm the only driver."
Just a casual observation but it freaked me out. As it happened the placenta moved so DD was NVD.Phew.!
So YANBU, probably just because at this time you are centred on what is going on with you, and some NHS staff are a bit detatched. (Some are eye-wateringly rude as well but thats another story)