I am really not trying to offend you at all, but I would never admit a student with your profile into a PhD program because of exactly the reasons you mentioned, most of all because of your very young age and the lack of research and work experience. You state that you are fascinated by research, yet you have not done any research so far.
Please don't get me wrong. I think your GPA speaks for itself: I am very certain that you have a great future ahead of you. I have not met too many undergraduates with a perfect GPA especially not very young ones like you. So I think that's awesome. Congratulations. Keep up the good work until you graduate.
I am only responding to your post because I am in the process of applying to PhD programs as well and I am at the opposite end of you. I might be too old. I am not sure what schools are looking for in doctorate students so it's hard to say, but my piece of advice is: get a masters degree in finance or an MBA first AND get your hands on some research. This will help you tremendously.