Its not a case of believing, or not believing in repression.

Brain function from birth to death goes through phases, and learns. Before a certain age (consensus seems to centre around 5 years old), 'memories' as they are to adults, can not be processed in the same way because those connections just don't exist yet. Your body and your mind know what happened, but you can't store and retrieve memories like you would as an adult not experiencing trauma. However, there are plenty of other proven indicators of childhood trauma (usually seen in behaviour patterns) that you may or may not identify with.

My suggestion would be that you read up on dissociation. You will quickly know whether what you are reading about refers to you or not.