I'm a Horrible Mommy!

I had my first "I'm a Horrible Mommy!" experience last week! Belle was lying down in my lap on the Boppy and my hand was behind her head. She jerked backwards all of the sudden and my thumbnail hit her head dead on. I knew it hurt her, but didn't realize that it broke the skin until a little while later when I rubbed the back of her head and saw blood on my hand! I looked and saw my thumbnail print embedded in her head! :( My first thought was "I'm a Horrible Mother!" I'm sure this is just the first of a few "horrible mommy" experiences I will have (but hopefully there won't be TOO many!).