There are strange cases of young children who claim to remember past lives. Who knows? But its interesting that pshycologists claim that children only become aware of themselves around age 3-5. So before then they are observers in a universe which they don't even know they are a part of.
For me nothingness is like when I had a general aneasthetic. I remembered nothing from the time I was out. So I reckon it will be like that when I die. Then if I end up having another life as a human, or an animal or a plant then it will be like coming out of aneasthetic but with no memory. Then slowly over time I will become aware of what I am, just like I did in this life. But there is no reason to assume that I will have another life.