What is the nature of her discomfort?
How was it caused?
So it is not caused by negligence?
Are you insured?
If the facts are as you say then you are not liable. She is just returning because she thinks that she can hit you up for money.
If there is no negligence then there is no claim.
It is very unfortunate she had a bad experience but you are only under a duty to not act negligently. You cannot stamp out risk entirely.
I would just refuse anything at all.
Even if she did have a claim though she would not get anything more than pain and suffering and you have covered that already.
Can I clarify anything for you?