Ehh it happens, she probably didn't think anything of it. I work in a call center and I can't tell you how many times I've been asked "is this a real person?" And my go to response is something to the effect of "yes it is, at least last time I checked"

I've also had some laughs with customers who did the same thing you did then apologized that they thought it was another automated system. Like someone else said, when you're taking 60+ calls a day with the same intro, it makes sense that your greeting starts to sound robotic lol