Usually rhinoplasty is performed at the earliest, 13 or 14 years of age in girls and 15 to 16 years of age in boys. Reason being, and it is a known fact, girls physically mature faster than boys and the collective goal is to perform surgery when at least 90% of the growth is complete. There are major growth centers in the nose that affect the growth of the face.
In cases of severe disfigurement due to accidents, surgery is performed in an attempt to restore the alignment of those centers. For lesser deformities surgery is deferred until after the teen stops growing. Rhinoplasties performed on teenagers and young adults, it seems, are often beneficial to the social development and self confidence of the individual.
In other words, this depends upon the stage of growth in the face as well as the gender of the patient. A qualified surgeon can better help you upon personal examination.