Hey, you're 16 now (most likely) you dont need her permission (i think). Have the operation, if its NHS then they arent gonna advise a costly operation are they? Even if its private they wouldnt jump straight into surgery without thinking of other solutions! They dont like operating on youngsters! Tell your mum you're having the surgery! If she wont let you, your body have it anyway! And from what i know, its not exactly a huge big operation thats a big deal! Get it done as soon as!