I've been a professional, in one way or another, over most of the last 30-years. If there's one thing that I've learned is that unless you are well known or have a specific outlet for your shots this is true, you probably won't make a penny.
Competition really doesn't come into it in your case. Only the pros in the same region or city are actually competing with each other. The web is a wide open medium but everyone, it seems, owns a digital camera and isn't in the market to "buy" anyone else's photography unless, as I say, that person is Ansel Adams or another well known professional.
Making money, more over a living, in photography is a difficult business especially if you're not affiliated with some larger company or photo business.
No one who truly knows photography is going to even look at the work of an amateur because of the normal lack of experience and recognition.
If you're truly interested in possibly making a living in this business the only way to start is by getting on with a company that specializes in photos - a news paper or other media. But, there again, you're up against people like me - guys and gals who have a photo resume as long as your arm.
From what I hear (I'm a Canon guy) Nikon dslr cameras are very high quality like my Canon cameras are and will serve you well - if you know how to properly operate them. Have you taken any classes in dslr photography? Have you done all your reading? Have you shot thousands of photos with a dslr? Do you have a body of work or at least a resume of work to show a potential employer? If your answer to these is no, then these are the things you'll need to even be considered for any position that will pay you to use a camera.
Sorry but these are the facts. I've lived with them for these many years.
I would liken it to say NASCAR. You're not going to get in the driver's seat just because you have a license to drive a car - am I making sense? Good luck.
