There's no set number to determine whether a nose is too big or not. Your height, the shape and size of your face and the skeletal features all work together to create a nasal appearance that either does or does not fit your face. Reducing the proportions of the nose is commonly performed with a high likelihood of success. You are still relatively young and so wait a few years to see if you feel your nose is larger than you like. By that time it may have become a non-issue. Best of Luck...
The size of a nose is not determined by actual measurements, but its size relative to the surrounding facial features. The nose on a man 7 feet tall would probably be huge on a woman 5 feet tall. Your nose may cntinue to grow for another 2-3 years. Consultation with a rhinoplasty surgeon will help you monitor your nasal maturation.
Everyone's nose is a bit diffferent. It is hard to say what is right for you without an exam. It is important to evaluate the relationship of the nose to the rest of the face. Remember men still grown until their late teens so you should wait anyway if you are thinking about having a rhinoplasty.