Don't worry about age- Gardening is one hobby where sometimes years of experience cant always provide the answers- Nature and the British Weather are the Masters im afraid!
To answer your question- Dwarf French beans generally are self supporting and do not need staking. However, considering the wet and windy weather so far this year I would recommend that you do provide some stakes-this will help keep the beans off the wet ground (and so lessen the chances of your beans becoming mildewy).
Do not buy expensive bamboo stakes for small dwarf plants. Have a look in your local supermarket for some fairly long bbq kebab sticks/chop sticks. These should be fine to stake your dwarf beans with-It has worked for me before and they are very cheap.