Yesterday was her last day to ship per DS rules (5 business days). Did you tell her you needed it by this weekend? If not, make sure you do so in the future if you need a rush on something, or need it by a particular date. Unless specified and agreed upon, the seller can ship any time in those 5 days.
You can tell her you want a refund, but seeing as how you say she isn't responding to your PM, she may not respond or at least in a timely manner. But it hasn't been a long time IMO, with you just PMing her yesterday.
I would send a PM stating you have yet to receive DC or any shipping confirmation from her, you needed the items by this weekend, and since that isn't possible with standard shipping now you want a refund. Then open a claim with PP if you don't hear back. At least that way you'll have proof you asked, if she hasn't shipped yet and decides to ship AFTER you ask for one.
I would also contact a mod if you can't get a response from her. And if she hasn't shipped by now.
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