Sorry if my original response sounded harsh. I'm only a few years older than you so I'll explain my reasoning. As soon as I saw the picture, I thought the look was inspired by the Irv Gotti look...which was inspired by the Al Capone look. The fedora + double-breasted look screams "gangster" or "pimp." Now, you may have come up with the look yourself, but to the observer, it seems inspired by rap music and gangster movies. Hence the comments of it being "affected." See this article
Other members have suggested tips on improving the fit. While I agree with the suggestions, IMO, the problem lies with the fedora + DB suit look on you. For someone your age, there's no getting away from the pimp/gangster association with this kind of dress...you may say that's the fault of the observer and not you.
On a more general level, I would suggest that you rethink the idea of wearing suits everywhere. Especially for teenagers, it just looks out of place. Every situation has a dress code, whether announced or not. Suits & ties are not within the dress code for attending classes in high school. Take some time to read through the forum, and you'll probably see that most members here wear suits IF it's part of their office dress code. Many members here would like to wear suits more often, but keep in limited to certain occasions because they were in a strictly business casual environment. Obvious disregard for dress code is not a good thing. You wouldn't wear shorts & t-shirt to an interview would you?