Could there be some misunderstanding? Maybe the person who spoke to her told her something which caused her to misunderstand you?
Nonetheless, if I'm you, I will stay clear from her. To have her dad call your mum to complain about this sounds quite childish to me. Why cant she speak to you directly about her concerns? If she's really behaving like the high and mighty type, then I have better people to mix around with.
Cheers up, okie? have a good wkend.