I honestly have no idea what my earliest memory is. I don't think people have earliest memories unless they identify it as the earliest memory at a relatively young age, and when thinking about the question many times while growing up, stick to this particular memory as earliest. What I think is my earliest memory is being in a pretty open field or backyard, when I was from 2 to 4 years old, and being called at by my parents, who were worried. However, after going back a certain point, these memories are heavily influenced both by anecdotes by my parents and by viewing pictures of my youth; these memories often are less so memories and more so figments of my imagination which is partly based on memory, and partly filled in with certain images and details that I have happened to maintain constant. For example, I know my age at the time because I knew where I lived at the time, and determined based on the years I lived there how old I was. There isn't really an extraordinary circumstance with this: it is just something that I vaguely remember, then asked my parents about when faced with the "earliest memory" question, and confirmed the existence this memory. I have absolutely no idea if my personality or identity was the same: I'm sure its not.
Yeah I know what you mean. My parents have told me a number of times about things that I did when I was younger. I don't know if it influenced my earliest memory at all just because mine was more associated with a feeling than with pure imagery. I think I have "memories" of my puppy, Heiyan, and I sitting by the fireplace sometime around Christmas, but I think that was based on photos.