I had to spank my two-year-old niece today. He wasn't listening and kept doing the same mistake over and over, defying me. I don't like to be physical, and I'm sure others would look down on it, but I didn't feel like I had a choice.
I think the right amount of spanking is OK.  I was spanked as a child and know I deserved it.  Hopefully you didn't take it to far though!
Yeah, I didn't. I try to use it sparingly so that it has more meaning. But he's not even my own child, so it felt wrong in a way. And I also felt like I failed because I couldn't get through to him without doing it.
Don't beat yourself up too much.  Spare the rod, spoil the child.  Your guilt seems to be from what other people might think.  You know if it was necessary or not.