'Please help I find this very confusing.'

Mike, the problem is that the word 'traditional' is used two different ways.

1. It means a song has a familiar, folksong form and sound. Verses followed by a chorus, maybe. Simple chords. It's either old or it sounds old.

2. It means a song it not copyrighted by the composer. Usually it's too old, and any copyright has lapsed. Such a song is in 'the public domain.' On a CD, for example, the credits will just say 'trad.' and we know it was not copyrighted. The composer is probably unknown, and use of the music is free.

If you wrote a song, it may fit under definition 1, but it doesn't fit definition 2. You may copyright it, no matter whether you do it acappela or use acoustic or electric instruments.

The purpose of copyright is to reward creative effort, and if you wrote a song, you made the creative effort.