Is she trying to gently let me down?

So, I was about to ask this girl I like to homecoming. I was setting up for the big question by asking her if she had any plans for homecoming and she was like, "Well, my mom's in town for that weekend and I want to hang out with her. And dances aren't really my thing". I don't know what to do, because I'm sure she got the general gist of where I was going with it, so... ya. Do you think that she was just trying to avoid going to the dance w/ me?