Utterly dreadful experience at WCA.

I have had two of these for ESA before. Both times the experience wasn't too bad to be honest, and the last time I was in and out of the actual assesment within minutes. This time it was awful. The woman assessor seemed to have no understanding of Anxiety disorders at all. And she was ferociously asking questions and tapping away like a lunatic. She even asked the question 'what are you anxious about', surely any professional knows that anxiety isn't about being anxious about something in particular
Every question seemed to be a way of tripping me up and I got completely flummoxed. And then she went out of the room for 10 minutes to consult another member of her team then came back again
No idea what was going on.
I just wanted to know if this is normal for WCA's?

Also any idea how long it takes to hear back from DWP? Unfortunately I feel like an appeal is going to be on the way and I want to be prepared