How would you know unless you put her in the situation of her letting you get a glance at some hint of evidence that she has feelings for you? If you don't want to "make a move", you are just going to watch someone else make a move and watch as she is swept away by him, thinking that it could have been you.

Women dislike men who do not want to make a move. Why should we make the move? We can simply wait until a real man comes along and makes the first move. In reality, we do make the first move, but we set things up so the man can make the more obvious move.

Think about it, she invited you to the ball. She asks you how you are, I don't ask my mother how she is. She's trying to let you get the hint, that she likes you. She's also waiting for you to get it! If you don't get it soon, she may find someone else that will. Time is running out.