A girl suddenly ignores me out of the blue. I Can't figure out why?

I became friends with a girl that works at Tim Hortons. I drove her home 3 times, she seemed like a real nice person. (Talked alot in the car!) She even had my coffee made for me as soon as she seen me walk in the door everyday! On the second night, she asked if I wanted to go for drinks with her. I said sure.. The next night she gave me her cell number. I asked if I could text her the next day to see what time would be good for her to meet up. The day after that, she texted me and said she's doesn't want to dissapoint me, but becuase of our age difference, she doesn't think it would be right. Now she's ignoring me all together. I have no clue where she would have gotten my age from! She told me her age afterwards. We're 8 years apart in age, I don't understand why she's suddenly ignoring me... I get the feeling this isn't about age.