She SHOULD refund you and shouldn't have to ask for it. But things aren't always like they should be. You are an honest person, I would be so thankful I would have refunded you plus some! If you feel like you want to ask for the refund go right ahead. She did say she would. It's kind of a tough decision since it's not a lot of money, BUT it makes me mad that you even have to think about asking for your money back!
No matter what you decide, I hope you have peace of mind knowing you're the better person and any of us sellers would be lucky to do business with you!