Driving etiquette

How about I talk about a funny experience I had not too long ago while in NYC? I was driving to a bar with my friends on the East Side. We arrived and were looking for parking, when 'lo and behold, there was a spot. My friend tells me about it, so I pop a U-ey. But first, I had to back up(I can't remember why). All of a sudden I hear a honk behind me and my friends are shouting all around me so I brake and look back. My friends tell me, "You almost hit that woman," so I go, "Ok," and proceed to do my U -(or K) turn. I get to the other side, and my friends are telling me that this old lady is giving me the finger. Well, in response I wave. Don't ask me why she is still on the other side of the street, when she could have gone through the light about three times at this point. So I hear some whining (almost like the old operator voice), and I roll down the window to hear, "That wasn't very smart" in her whiny, "Why don't my kids ever come to see me?" voice.

So I try to be nice (Hey I cried in "The Notebook", and actually have a soft spot for old people) but she kept on saying the same thing. So I finally lost it and said, "SHUT UP!! No one is listening to you!!!" Now that I think of it, I should have thought I am probably not the first person to tell her that. Or I could have responded, "Hey, I loved your work in Cocoon!" I was raised to respect the elderly, but dude, she gave me the finger!! And she totally took for granted that I am not going to get out of the car and beat the Metamucil out of her! On a Saturday night in NYC, and I am not alone. She should be more careful with her words is all I'm saying. Any thoughts on my behavior? Was it reprehensible?