If you have it in writing (ie email) that she confirmed she would cancel the order and refund all your money without a problem, then n, she can't just send you the nappies to fix it.
She MUST refund your money, given she has agreed to cancel the order and refund, and hasn't already sent you the nappies.

Send a final email, in very firm, clear and formal language, and let her know this is the last communication you will send her, give her 24 hours to refund the money and forward the transaction and receipt details to you. any long and you will take action with your bank and credit card company to recover the funds.
Let her know you have all her emails confirming the order was canceled and payment was to be refunded as proof that the "binding contract" was actually dissolved by mutual decision. Put all of your contact details in the email, so she can't say she couldn't contact you.

If you still don't get your money back in 24 hours, call your bank and your credit card company.

Good luck!