You should register it if you want to do anything with it. I wonder if they check that when it's registered to see if it's already be done before.
Just out of interest, is there electronic equipment for writing music because writing a score by hand is time consuming.
How can it not be my original if I made it up out of my head.
Does the US still require this? Most other countries don't have any registration - either as a requirement or an option.