As many of the people replying have said, tunes, melodies, and word patterns recurr all the time - what makes the song/tune interesting is the personal aspect - so enjoy singing it, and maybe write some more.

As an interesting anecdote, David Lindley, an American musician made a set of wonderful CDs in Madegascar, where he recorded and played with many local musicians. One of the tunes on one of the CDs (the first one I think) is some local Madagascar harpists playing a tune, hich is note for note an old Irish tune - there is no known link between Madagascarf and Irish culture - Music is a magical and spiritual thing - forget about copywright and enjoy the experience.

Regards,

Colin Manning (colin@ework4.com)