Did I take it too far?

So I need your personal views whether or not I took this situation too far or not.
Today, for my new job (yay!) I had to take a u/a test (I had to pee in a cup). However that was not the issue. when all was said and done, I was very pleased with the result (very clear).
However, while I was walking out of the backroom to the exit I hear a very excited "kimber!" as i was turning around my question I posed to myself was who do I know that calls me kimber? So I turned around and looked this very excited girl up and down and had no idea who she was. i tried real hard to pull off the "...oh...yeah...hi! how are you?" she seemed so excited to see me that she did not even notice my lack of enthusiasm due to the fact that I had no idea who she was. She carried on with "oh i can't believe you were going to walk out of this office without saying hi first!" I was so completely lost at this point. Stunned is probably a better word.

She then asked me the normal questions like what are you up to these days, the tricky part for a response was, what in my life does she care about? Church, school,...ect. I had no idea. So I explained my reason for getting a drug test wich seemed enough for her because she chatted on about her job. A moment later we were interrupted by a nurse saying "oh you two know each other?" I just looked at her and smiled unintelligently and looked at my new/old friend and waited for the response. I think my mouth dropped a little when the response was "oh yeah she is my brothers ex girlfriend."
ok a few problems with this statment. 1. I have never had a boyfriend 2. i have not lived in portland for quite some time 3. i had never seen this girl in my whole life
at this point in the conversation I had made the decision to be as non-commital as possible for the sake of the poor girl when she realized i was none of the things she claimed me as.
So while I was looking for an escape route to this continualy awkward (only for me) situation, she turned to me and goes "kimber you really have changed" (yeah lady because you have no idea who I am but at this point I was in far too deep to turn back),then she decided it was a good idea to grab my hand and and take me over to her desk to show me her children. she showed me the youngest and was like look shaila, you remember her right?
i just stared. her response to my blank look was (or what i would like to say, non-commital look) was oh of course you don't! she was just born. (silly me). Then she started talking about her other girl. Her words were "of course you remember her!" with my reponse of "oh wow she is beautiful"
"she asked the question she has grown huh?" my response "yep she sure has grown i am sure"
while our little reunion was winding down there were a few more awkward questions about her dad and her brother (apperently ex boyfriend) that i (with skilled) avoided.
while walking away after our departure and promises to see each other again my last words were "tell her brother I say hi". I really did not want her to think I was bitter.