It is not usual to have difficulty remembering one’s childhood. Many people have limited memories of their early years. Rarely do individuals remember every detail about their early life. It is difficult to know why this might be.
Individuals who have difficult childhoods or who have experienced a trauma often report limited memories. From a psychoanalytic perspective one reason for this may be that the unconscious mind blocks these memories. The memories may be blocked because the individual is not psychologically ready to handle difficult events or experiences. Those memories may be slowly revealed to the individual over time, when they are psychologically able to handle them.
What an individual cannot remember consciously sometimes is revealed to them through dreams. Dreams are produced by the unconscious mind and can reveal important personal information. You may want to keep a notepad next to your bed and write down your dreams immediately upon awakening.
Hypnosis is another way to explore the unconscious mind. If your lack of memory continues to be a troubling issue, then you may want to consult a trained certified professional who specializes in the use of hypnosis.
The psychoanalytic interpretation of your inability to remember certain aspects of your childhood is that you are not psychologically ready to deal with these memories. When you are, those memories may be revealed to you.
I would encourage you to study memory recall and memory research in general. Those resources may provide exercises or tips that can help increase your ability to recall early memories. I wish you the best. Please take care.