Update:
I found out that she had done what I suspected. It took me about six calls and the runaround, but I finally got through to them that it was fraud. I guess they didn't want to be involved so they cleared my account up, sent me a refund for the overcharging, and zeroed out my account.
Then, I had to deal with her by letting her know that I was onto her. She's funny, she swore to God that she didn't do it, but at the same time said she would call to straighten it out. Which she did, because the next day her name was off of my account.
Unreal.