I'm not small for 16.  I have added nearly an inch to my arms for three consecutive years.  At this rate, I will have solid 18" arms by the time I'm 20.  
With my classic lines and what I'm sure will be superb conditioning, I have no doubt that I will be among the best in the amature national scene.  I know it sounds cocky, but I am just very confident. 
I have no aspirations of turning pro though.  From what I understand, these guys don't make much money and have poor health.  Instead, I will become a successful business mogul after competing for a few years.