Why did she walk the other way when she saw me?

I'm 22 and she is in her mid 30s. We are both women and live in the same apartment building. We both also have dogs so I will see her walking her dog a lot. Whenever she used to see me, she would say hi and start chatting with me and I would always be really shy because really confident older people make me nervous. I got the feeling that she was attracted to me because she was always invading my personal space and would go out of her way to say hi. Anyway, I didn't fully know what she looked like unless her dog was with her until a couple of days ago because I never paid attention but I was at the store waiting for my friend and I said "Hey! you have a dog named bernie right?!" and kinda shook her hand and she seemed not as forward as usual and I'm not sure why. Then I saw her this morning while I was taking my dog out and she was with a friend walking her dog and saw me and started walking really quickly the other way...then her friend looked back at me. So, I'm just confused...did I do something wrong?