Duffy's shyness almost stopped her becoming a singer.
The Welsh songstress - who picked up the Best Pop Vocal Album prize for her debut LP "Rockferry" at this month's Grammy Awards - nearly chose swimming over singing because of her nerves.
She said: "As a kid, I never wanted to be a singer - I was far too shy. I used to be a good swimmer but I got picked on in the pool."
The 24-year-old pop star recently revealed she would like to swap her retro 60s sound and make a more modern record now she has established herself on the world music scene.
A source said: "She is keen to explore a Mariah Carey or Christina Aguilera style of album. On the next record, Duffy can afford to be a bit more experimental now that she is assured her position as a singing force to be reckoned with."
The "Mercy" singer is currently rehearsing for her performance at this week's BRIT Awards - which take place at London's Earl's Court on February 18 - where she is up for a clutch of prizes, including British Female, British Album, British Single and British Breakthrough Act.
(China Daily/Agencies February 16, 2009)
