yes i had a similar experience, it was with a pdoc tho, wont go into long winded details but yes i have been told there are things wrong with me that were not and yes they were very cold and almost cruel about it after spending one session with me.
My advice would be to let it go and forget about her, some people (professionals) have no bedside manner and make snap decisions based on their own personal experience, please don't take it to heart that all mental health professionals are like this, they are people and prone to faults just like us, its very hard when we come across someone as such (especially when we are at our worst)
You did nothing wrong and your feelings are very valid about this IMHO.
Don't let it bother you and move on noting to yourself that this person was just not the right fit for you. They are probably used to emergency and critical cases. It doesn't diminish your feelings or your struggles.
Hope this helps a little this thinking helped through those first few months of dealing with these kinds of people