Work Ethic

I recently started a FT position at a defense contractor in the Deep South (Saints/Pelicans). I always believed that I was driven and resourceful, and I started with the understanding that it would take me some time to learn the nuances of my job. But my interest has waned sharply. I still deliver reports as soon as possible after they're requested, but I don't have much to do. So I surf the same websites every day (ESPN, Reddit, WSO), pass the time until lunch, and try not to fall asleep at my desk.

I took this job as an opportunity to gain experience for the finance career that I would rather have. I was set on the pay and prestige of IB or AM. Now I'm not sure if I can handle the office time. I rarely exceed 45 hours a week and I still want to GTFO of work well before I'm done. I've come to realize that I'm somebody who works to live, and not the other way around. For a while, I couldn't get why someone wouldn't pick a lucrative career, even if it was a desk job. To me, a job is just a job now.

Is every career like this? Would a career that I'm more interested in keep me stimulated? Does a full-time job become easier after a few years? Should I just enjoy being young, before the hangovers get worse and getting fat becomes easier?