Dude, do you wanna look like Popeye or something?
I mean big arms and chicken legs? What about the rest of you, a good bod needs some symettry. With all that chest work, you are going to end up with a big imbalance in your back. Not to mention the lower body. Plus, your chest and arms must be so used to the motion of a PU, the muscles have adapted, it will get to the point that those PU do nothing for you.
If you have to do all those PU because of the army thing, well, you gotta do it. But lay off with the extra ones. Start training your whole body, you'll make far more gains in strength and endurance.
Do you have access to a gym? Start with the primary lifts: squats, deads, rows and benches. And chins/pull ups.
At 16, with a good diet, you'll see gains in strength and endurance in no time.