This is a classic avoidance technique. Sometimes kids get sent to a psychologist because they lie all the time for seemingly no reason, to later be directed towards a speech pathologist because the psychologist realised it was actually a way for the child to avoid specific words. You don't have to feel guilty for doing this as this is simply your brain attempting to find a solution to a neurological event. With time and with enough practice you will find ways to express yourself more easily while avoiding creating falsehoods. Be patient with yourself and try to remain in the spirit of self-compassion.