I think this customer has had a bit too much Crown Royal....Your price was more than fair.
Some people are never happy.
Be prepared with a professional rebuttal if any other customers ask you about this incident. You were clear about the cost in the beginning, but she must have misunderstood because there was some confusion when you gave her the bill however the price was fair for the quilt presented in the less than ideal shape that it was and the customer did agree and pay the bill.
Stay professional no matter what you hear that she may have to say. I used to have a small business doing custom design work and sometimes customers can get some odd ideas about how a transaction went down if they aren't pleased for whatever reason.
Also, off topic, don't forget to take pictures of all your completed jobs for your portfolio!
Watson