I never realized I was BPD until the diagnosis

So, I've been in the mental health system for about five years now. And its always gone something like this for me:
Hm im having these problems and they remind me of this illness...*I do some research, discuss with therapists, go for a while undiagnosed before eventually being diagnosed*
And thats happened with all of my current diagnoses.
But then, a couple days ago, I was with my therapist and we were looking through notes from a recent hospitalization to try to find the phone number and/or name of a DID specialist who I was recommended but had lost the paper with his name and number. And as we were going through the notes together I saw a little section, I didnt get to read much of it before she scrolled past it but I read "Shows symptoms of borderline personality disorder and..." and later I saw that at the end of the stay I had the diagnosis of "personality disorder NOS" added to the list.
And I was...confused. Because I have known about BPD for a while, I'm pretty well educated on different mental illnesses because I run a mental health blog. And I've looked at personality disorders before and none of them had ever really seemed to describe me...I had no idea I showed symptoms of BDP or any other personality disorder. And I'm still confused and lost because I just never saw this coming...and I'm wondering what things I said or did during the stay that led them to believe I have a personality disorder. Because of my DID I have frequent black outs so..i just dont know. I'm just really weirded out that I never saw this coming?
-Kai

Hey man I just read your story. I can see why you'd be weirded out. I mean, you think you personally don't show symptoms of that and it's like last thing on your mind. Then, next thing you know, the doctor's all like... So yeah bro you got BPD soz. Like, the ###$ do you mean I got BPD? I don't see how any of my actions would've tipped them off at me possibly having BPD. I'm sure you're going to find out more in the future. Either way please take care in the time being.

HH, if there are notes in your files about BPD NOS and no one has discussed this with you, remember this: therapists are people, not machines, and like any other people they think about the information they're getting just like you do, especially on diagnoses like BPD, which many therapist will be reluctant to diagnose…and if NOS is on there too, it's like someone just thought, "$#%^, I don't know, looks like BPD traits to me."

On top of that, you say these notes were the result of a hospital stay. I don't know how long you were there, or what your treatment was like, but it sounds like you have enough doubts about the notes to ask a lot more questions about it. Talk to your regular therapist to get a more definitive perspective. That's the only way to be clearer on the subject.

Take care of yourself.