The one thing I learned about the design industry is its not about the education you received, its all about your portfolio. Learn all you can and bring in the knowledge of graff into your design game ( color schemes, balance, structure).
The thing you all benefit from is the fact that you already have experience with typography, composition, and color theory. Transfer your knowledge of what you already and apply to your design work. Learn some fundamentals, and lose your ego. Attitude is huge and networking is probably you best in. Its very competitive and it might take you some time landing a cool job. I currently make 70k and am an Art Director, But I didn't start out as that. I landed a production job and worked my way up. My advice is to take any job you can get at a reputable design house and work your way up from there. Make yourself an asset to a company then bring in your skills to show them you more than just a production artist ( which isn't a bad thing -- production can be cool too). Show your stuff to as many people as possible and have fun. Also, a lot of companies are looking for people with the basic skills for print. Someone who can build mechanicals for print. So another thing you might want to learn is not just design, but the production aspect of it.
And lastly, just keep designing. Do tutorials and learn as much as you can. The web is a great resource, take advantage of that.
word, have fun
Oh about selling yourself...I feel you on that. I didnt want to either. Playing the bullshit game is something I'm not made of. Let other people do that. If your good you wont have to "sell" yourself, or your work. Others will. Then you get to a level of comfortability and speaking about your work wont feel like bullshit to you. Its all about your comfort level and confidence. If you know you are good at what you do, then fuck everyone else. Its a game, but we're all players, shit. Its a hustle, but we;re already hustlers.