No your not crazy. Etsy is crazy and keeps changing everything so often its hard to keep up.
If a customer leaves 3 stars or less, then you can leave a response. So before she changed stars, you could have responded.... however, once you leave a response, etsy will not let the buyer revise the review. So, its a catch 22. We never really get to have any say in the issue. Unless, we work something out with the buyer and beg them to change it.(also... they only have 60 days to alter any feedback)
I had a buyer leave me 3 stars, which was horrifying to me. She told me her earring broke, but she threw it away. I told her I accept exchanges only if she still has the damaged item and would send it back to me. So then she leaves me a review saying "my earring broke, and this seller wouldn't give me another pair, then I wore the other earring the next day and it broke!" It was very suspicious because I've never ever had that particular style of earring break(I assume that she actually lost it, and wanted a new one), plus, who wears one earring(after the other one breaks)?
So, when i received the feedback, I figured I would just send her a new pair, only if she agreed to fix the feedback when she got the new pair.
So eventually she changed the stars, but still said negative things, without mentioning how far out of my way I went to send her a new pair, not to mention pay for shipping and all. It was an ordeal.
Now that I've been selling on etsy for a few years, I'm starting to learn about the different kinds of customers that are out there:
60% don't care, don't know how to, or are too busy to come back and leave feedback.
35% are so grateful for their purchase and leave excellent feedback and compliments. Also send "thank you" letters!
4% want something for free, by lying about not receiving packages or by saying something broke.
AND 1% are just seem to be mean... I assume they are just depressed people.