My earliest memory is moving into my house. I remember standing around in the door way and my dad's coworker was helping him bring a sofa inside. It was bright outside and the floors were wooden. I think I was around 4. This is probaby memorable to me because it marked a new beginning and I lived in that house for about 8 years afterwards. I feel continuous with the person in my memories. I feel like me for as far back as my memory can go; I reason that since it is my memory the person must be me, regardless of how much I've changed. My personality is definitely different and I have matured. I am more outgoing and experienced than I was at the time.
It seems like significant injuries get ingrained in people's memories quite well. Though this little cut may not seem very significant to most people our age, you were very young back then and in all your [very short] life, you have never experienced such an injury. It also probably helped in remembering this incident the fact that your moved to a new home, which is really big deal for a young child.
I remember when in my early days in America, I tried to act like the American hero Superman, and ended up breaking my nose and going to the hospital. New homes and injuries make memorable memories!