Spending $15k on your first car is a really good way to lose $15k.
At 16 it's impossible to know what you really want from a car, what you will enjoy owning and driving as you have no experience beyond what you learned to drive in and what you read in magazines.
Your first car should be something really simple, but with potential for lots of fun.
That means it doesn't have to look good or go fast, but should have room to carry 3-4 mates/girls.
It should be cheap to run, and if it gets damaged should be easy to fix, or no big deal.
Spend $2-3k, keep the rest of the money for booze, girls and food (or a house deposit if you want to be responsible) and look for something like an old Honda Civic.