We used to be so worried when we took our son to the pediatrician, and he had bruises all over him. Our pediatrician (whose kids are all exactly a year older than ours respectively) said that he worries more when kids don't' have bumps and bruises.
Accidents happen. If you're being negligent and letting your kid run around while you're not paying attention, then you are not a good parent. But, if you're giving her a little independence, and she falls (1 year olds are still very unstable) - it's part of the learning lessons of life.
You're not a bad mom - that's evident by the guilt you feel. A bad mother wouldn't have any remorse.