J.G.
Most kids I know of didn't start walking until 13 or 14 months, and if I remember correctly, doctors aren't at all concerned until after 16 months. Some kids are "perfectionists." They don't really want to try a new skill unless they think they can do it right. My son is like this. He didn't want to write his name until he could do it perfectly (he practiced when no one was watching). He wants to be able to tie his shoes, but he doesn't want to screw up. Makes it hard to practice!
Try not to stress. She'll start walking before you know it.