Just a heads-up: as I understand it, that is not allowed. From the website:

Can I lend my Citi Bike key to someone else?

No, your Citi Bike key is not transferable. Inappropriate use or sharing of keys will result in membership termination and any overtime fees and/or potential damages charges will be settled against your credit card.

You said that you took out the bike yourself and let her ride it; but I think that that's essentially the same thing as lending her your key. So, I believe that your membership could be suspended for that.