Actually Yes you are. A Solo card is a form of debit card. This can be issued to people from the age of 11 by NatWest or 16 from HSBC.
Solo is like a switch card in that it takes money from your account almost instanteonsly (sp?).
You are not allowed to have a credit card. This is only available to over 18 year olds.
Interestingly, credit is available to you if you are over 14 years old and in employment if it can be proved that what you need is a neccessity (eg a 17 years old could "need" a car if they were working shift work with no bus service). Trying to find a lender that will actually lend to you though is another matter....