As a fellow procrastinator, (so is my DD), I think you have an edge at USNA.
You've managed to earn an appointment to the USNA probably as a "procrastinator". Would you/could you do better if you weren't a procrastinator? Maybe, but the implication is that you have a little bit of extra "gas in the tank" that you haven't tapped into yet, because you procrastinate (that's a good thing).
More likely, your are a "Competitive Procrastinator". There is a fair body of research that suggests really successful people, ( as a USNA Plebe-to- be you qualify for your age group) are often "Competitive Procrastinators" def: Procrastinators driven to succeed who have learned to take advantage of a brain that is
100% focused by the panic of a deadline. This really something you have going for you particularly in the context of attending the USNA.
Please take a few minutes away from the class work you should be doing

and have a look at one of my favorite TED talks. Its kinda funny and very insightful re procrastination. Its worth your time---I'll wait, seriously stop now and watch this before reading more of this post
As near as I can tell, EVERY MID GETS TO MEET THE PANIC MONSTER MULTIPLE TIMES WHILE AT THE USNA.
Over the course of her time at the USNA DD called --sheesh! she called a lot of times, while she was pulling an all-nighter. Her Panic monster was present in those times but she knew how to use it, not be genuinely panicked by it.
During her plebe and 3C yrs she called a couple of time exhausted around 9pm Pacific time to ask me to give her a wake-up call when I hit the rack at 12 (3AM her time). I'd call and make sure she was truly awake. DD would then resume work through to completion of a paper or exam prep. But like you, my DD was well acquainted with The Panic Monster, its appearance didn't phase her and she was confident in the work product/studying that she did with the monster present. DD procrastinated her way through the USNA and did pretty well.
Many of your classmates will have to deal with their more ordered approach to getting work done being blown-up by the volume of tasking coming at them. You will have to adjust to more frequent appearances of the "Panic Monster" but not the monster itself -------------------------he's an old friend you know how to use him.
More Good News For You:
Here's what your teen-aged
"Instant Gratification Monkey" will look like at the end of Plebe Summer.
Life in an adult meritocracy, working/studying in friendly competition with your classmates for seats in airplanes, spots at nuc-school, medical, Intel, or just making grades to stay in,.... that won't end until service selection during your 1c year. Scholastic challenges, leadership challenges and messaging about duty /responsibility, to yourself and your shipmates will be pretty much constant.
Dead lines will be frequent and regular (the Panic Monster always lurking close by). Your Instant Gratification Monkey just wants to have fun, he/she isn't intentionally self destructive. Expect it to keep a low profile as new tasks frequently emerge from the Fire Hose; (your not stupid, you will adjust).
I like your odds, and if I were you I wouldn't be too worried.
I am sure some others here are thinking I have just damned you to failure by minimizing your problem; so one procrastinator to another, here are a couple of suggestions to manage your procrastination.
1) In my life, my 100% focused procrastinator mind generally does good work. The problem has been that a 100% focus on an immediate task has sometimes caused me to overlook, forget, miss other tasks and obligations. Both DD and I keep a calendar with us most of the time. We are both old fashioned in that we write things down in a calendar notebook. keeps us from missing stuff when we are holding the Panic Monster at bay. Highly-Highly recommended.
2) There are tons of great opportunities for your free time at USNA. If you are really worried about making grades, make study groups with regular meeting schedules a priority. Ones where you sit at the mid to top of the group in terms of proficiency. The Monkey might blow off study for you but mine will support attendance as a duty to others rather than work I need to do for myself. You will learn by teaching and it also will serve as a quasi study hall.
3) Find a friend, family member on the west coast who you can call upon for a wake-up call at 3-4-5 AM your time in Maryland. Not saying you should figure on imposing regularly or pull all nighters often, but when you are in that situation a 2-3hr nap that you know you will be woken from to study/work some more can be golden.
4) Frankly, avoid courses that depend on incremental and repudiative learning: Saaaay Arabic or Chinese language studies. Crushed me in college; crushed my DD at USNA
Congratulations on your appointment, and good-on-you for choosing a path less traveled by. Now if you'' excuse me, I have some work to do on a couple of contracts; ...... right after a play a round or two of Battle Supremacy on the net.