Ok so here is the "problem" I am facing....?

I have a friend and she has a twin sister and a little sister. Her twin is 14 and her little sister is 13. Lets just say for questionable terms that I did like her little sister. Would that be weird in any ways. We were talking three nights ago and she told me not to tell her sister I was talking to her. And of-course I forgot and told her older sister. She got mad at me. Does this mean that secretly has a crush on me?? Also when we were talking she told me about her ex and she asked me for my facebook. Im 16...