Plastic surgery is used to change the appearance of bits of your body. It is is available on the NHS for specific problems in children like for those who have a cleft lip or palate, or following injuries like burns which have left people disfigured. Nowadays more and more people are going for changes to their nose, lips, breasts or whatever bit they choose - but this can be expensive and does have risks - like getting an infection. If you really really think your big nose being smaller would change your life you can at least ask to see a plastic surgeon but if you are still young, they are not likely to do anything. Also remember you can't change it back... and there may be easier ways of changing your life and making yourself feel better about yourself.