didn't send my ring

[dstearnes53.2013]

i bid on the ring and won. i paid for the ring and then she refunded my money and relisted the ring for twice as much and asked me if i wanted to buy it as the new increased price. I didn't know ebay allowed people to sell an item and then take it back and relist it for twice the price i purchased it, and then asked if i wanted it? is this a common practice?