I searched for all the questions around here and i still couldnt find how to fix this. Im going mad already. I've done tutorials and everything i could, unwrapped, set materials, create image, and still i cant paint on my mesh. it doesnt matter what i do, i cant paint on it. i really need some help to how to be able to paint the models, because im trying to make a game and im stuck here, cant move on on anything until i finish this :\
Edit: so it looks like your problem was the Face Selection Masking option (on the horizontal menu bar, the icon with a red and whithe chessboard), it allows to paint only the selected faces.
First you need to create an Image Texture in the material so that you can paint on something: In the Node Editor, enable Use Nodes and make a chain with your Image Texture node > Diffuse > Output.
I can't see your "PlayerSkin" image, maybe it's because it was not packed with the file. So you can use this image, if it exists, or another one, as the Image Texture.
Also, your unwrap is very special, you probably made a simple Unwrap but it doesn't respect the proportions of the topology. To directly paint on your object you can simply use the Smart UV Project option when unwrapping.