Relax.
Save the worry for senior year. In time you will realize that junior year is really all the work you SHOULD have been doing sophomore year. It's a tough year because this is the year when it REALLY matters, not because classes are harder. Remember all those foundations classes you took freshman and sophomore year? They prepare you--or at least, should have--for junior year, that's their purpose.
Junior year was a whole lot of work, but looking back, it was the most fun. You're finally one of the "older kids" on campus and at that point, I feel that everyone gets a better academic sense of self, by which I mean you know your study habits and your limits; you know when you're better off sleeping than pulling an all nighter, and you know how you can dig up some facts from a foundation course to BS your way through an in-class essay
.
You don't need to worry. All you need is a warm bed in which you can get a good night's rest, and maybe a roommate/neighbor to make sure you're awake for class! If you're studying and feel those HEAVY eyelids are foiling your studying efforts, go ask your roommate/friend to wake you up in 15-20 minutes. Take a break, have some caffeine, and resume. Or take a shower and stretch in the warm water--my standby wake-me-up method!!
Good luck
