You're going to have to explain in more detail what exactly you want other than "help" which is kind of vague. I think those mountains could be there, if there were perhaps a volcanic hotspot underneath that area (a hotspot is a point where magma bubbles up in the middle of a plate.) It could explain the small islands to the north-east as well, though hotspots usually form little "chains" (for example, look at Hawaii.) The oldest mountains will be the shortest (due to erosion.)
One stylistic thing that immediately jumps out at me is that the lines of your continent and water are much thinner and more pixelated then the lines for your symbols (mountains, trees, etc.) so you may want to make these lines thicker and smoother to match.
Unless you ask more specific questions, that's all I can say, but you can only get better by doing a little research. It might be worth it for you to read the wikipedia article on plate tectonics, then go look in the tutorial forum for guides in whatever area you need help.
I agree with Crudus's advice about the lines. I think some of what's at play here is stylistic rather than purely technical, but sometimes it can be tricky to make Photoshop bend to our will :) You should try to get the trees to blend in organically with the mountains as well, rather than pasting the mountains on top of a forest. Try to think how they would grow around the mountains; they also seem flat compared to the detailed, huge, jutting mountains. Look around for inspiration and ideas, try to see how others did what you are trying to do, or look over tons of maps and try to think what that person did that might be relevant to what you're trying to do.
Hello again... I've studied a little of the manuals here on Cartographers guild, and changed a little the way i should draw my first map. I want to present Helácia (or at least some geographic features) a continent from this world im drawing now. Its on 40% of his full resolution. I hope you could gave me another tips and advises... Thanks.