even before you said you were 16 i could see it in the work. not saying that's a bad thing, just don't worry so much about producing masterworks or being able to sell anything at this early stage in the game. enjoy painting and making for its own sake right now, worrying about making a living and doing what will sell is what leads to terrible art. and there is more than enough of that out there.
as for the technicalities, your applications is not so good. that crinkling on the red is a skin that has formed because you slapped it all down in one go, and now it is dry on the surface and wet underneath. it will not dry out now, and any rough contact will break that skin. of course maybe I'm wrong and its just the texture of the black paint underneath, which brings me to another point. learn to take decent photos of your work. if you want critique we need as much visual info as possible
http://www.youtube.com/watch?v=Vpj28da03JQnext thing, your colors. those are tube colors. you want to talk professionalism, no painter in their right mind(without a good narrative reason) will use tube colors. they look artificial and disingenuous. it tells a viewer that you are either to lazy or too afraid of your media to experiment(and I'm betting its the latter, I'm sure you are very committed, and paint can be scary)
never use tube blacks, unless again, there is a good narrative reason for it. you can mix a very effective black from ultramarine blue and burnt umber in equal ratio. this can be modified to be either warmer or cooler with more or less of each, or brought to a very dark tonal value in equal proportion. it has a it more life to it than just a regular old black.
that red, what is that? looks closest to cadmium, but i reckon it was probably from a big generic bottle of "red". get yourself a cool red like alizerin crimson and use both that and a warm red (cadmium) to get a bit more life into it. earth tones can work wonders too. mix your reds with a little burnt sienna or yellow ochre depending on what you want and how it looks in the piece, it'll add nuances and life like you wouldn't believe.
below the black, is that bare canvas showing? it actually seems to work quite well to create contrast with the black, but is it an intentional choice? consider putting down a ground before you start to kill that white, it makes it easier to get a tonal range going.
after all that, i have to say, i like you stlye, just go for it and don't worry so much. painting isn't something you learn overnight, it takes years. don't be worried about selling shit or finding work, if you are diligent, and you give a shit it will happen. be prepared to work harder than you would if you were in a "real" job. the reason those abstract paintings on ebay hardly sell is because they are, well, shit. the people making them haven't a clue what they are doing, and it shows. they simply slap paint down in a bizarre parody of what they think "abstraction" is. just because that doesn't sell well is not indicative of paintings overall value(which is not financial to begin with). and dont go studying " realism" just because it might get you a job in "videogames". it wont. and even if it did, do you want to spend your time drawing fucking orcs for plebs in some shitty free to play MMO. the world needs less of that. of course if that's what you want to do, go for it, just be aware that there are many kinds of art, and many art worlds that you could be a part of.