If she hates the subject, she might want to study it harder, to make sure she gets enough information on it. I know when I hate a subject (maths), I want to study it harder to make sure I take it in, or else I know I won't ever end up doing it, and probably fail it all together. She could be busy, too, and she might want to let you down gently, or said what she did because whatever came up is important, and she might be hoping you'll believe it and understand.
I don't think she has anything against you, though, as she told you she wanted to make plans. Something just probably came up and she doesn't want to feel like she's let you down or a bad/unreliable friend.
She does like you though, because if she never, she wouldn't have came up with a pretty reasonable excuse, and she wouldn't have asked to make plans in the first place. Unless something bad has happened between you guys and she's mad. Which you never said anything about, so I doubt it did.
Just ask her if she can make plans some other time; maybe ask her if she wants to go to the cinema or into town on Saturday or something, and see what her reaction is.
Don't distance from her, she probably just didn't want to let you down. :)
Post edited at 8:05 am on May 6, 2008 by PineappleKiss