You can be a successful professional if that is your goal. Are the guys who have trained their whole life going to have an easier time of it? Absolutely. That doesn't mean you can't make it happen.
There are late-coming successful professionals in just about every sport. College walk ons playing in the NFL for example. Basketball players transitioning to football in their 20's.
You are easily capable of becoming professional if that's what you REALLY want. And I mean really want. Sometimes people think they want something before they know what it takes. Set goals for yourself. Talk to your trainer and ask him if it's feasible that you could compete in amateur competition after a year of training. You'd be 19. 4 years of amateur work and you're a pro at 23-24 with a decent amateur background. Will you be the youngest champion ever? Of course not, but you might be champion one day, if you want it.
How Bad Do You Want It? (Success) HD - YouTube