I'm not at all new to knitting; I'm nineteen and have been knitting since I was ten, but I've never used circular needles. I just bought a pair of circular needles today to try to teach myself how to use them. I have a pattern for the scarf I want to make but I don't want to start on that until I'm sure I know how to use them. The needles are US size 8 and 29" long. The pattern calls for 12"-16" and they were the only ones I could find at Walmart in that size. Can I still use the 29" needles to make the scarf? Or will I have to find different needles?