Cynicism or Craziness?

This morning I took Girl to school ten minutes early so that I could make it to Boy's band conference. I was really only there to write a check but that is a different story.
Normally Girl gets to school at 8:20, I take her right to the preschool room and leave. Today she got there early and had to go to the gym first. This meant we got there as the older kids were arriving. I parked around the block and walked up to the door.
Just as we were approaching the right door, this mom with two kids, started shouting "Hi! How are you? Good to see you!" I didn't know her and assumed that she was talking to the woman walking behind me as it was a very enthusiastic greeting for a stranger especially when you're about a quarter of a block away.
After depositing my daughter in the gym, I started walking out. As I got to the hall, the enthusiastic stranger stepped out in front of me and started talking "Hi! I'm Crazy* (*named changed because I was so thrown off I forgot her real one). I've not seen you here before! Is your little girl in preschool!? That's fantastic!"
After I satisfactorily and politely (I'm not a monkey) answered her questions I set off feeling off kilter and felt like I had just made a trip to the loony bin. She was sooo cheerful and enthusiastic for 8:15 in the morning.
I hate that I feel like this. I'm sure this exchange was her attempt at being friendly to a new parent. I, however, am not a small town girl; I grew up in Chicago and feel weird when removed from my protective anonymous bubble that is given to everyone in a big city. Also, she was so freaking cheery, it was like talking to Mary Poppins on crack. I know that I am being bitchy; you don't need to tell me in the comments, but the whole exchange made me uncomfortable that I don't think I'll ever come before the preschool room is open again.