Hi, I'm just getting started, too, and I hear you on wanting to "do it right" but not having the resources. I'm eating in a chow hall (cafeteria for those non-military folks) in Baghdad, so to an extent I'm at the mercy of whatever is being served. Like XYZ said, just take it easy and do what you can do. As for workouts, I've found (before going primal even) that what worked best for me was more along the lines of the primal fitness laws anyways - move around a lot at a slow pace, sprint once in a while, and lift heavy things. What I've been up to lately has been the starting strength routine by mark rippetoe (3 days of lifting a week of heavy barbell lifts focused on squats, deadlifts, bench press, shoulder press, cleans) coupled with lots and lots of pullups. I augment that with lots of walking - I wake up in the morning and walk for a couple miles, and try to work in some walks during my day (walking to & from lunch, etc). On the days I don't lift, I'll do some sprint work or maybe a time trial (2miles or a 5K for time). I try to mix it up when I can with some yoga, or punching a heavy bag. I also play on the unit softball team, and run most of the 5K races they have on some weekends. And I always get an occasional "day off" when work gets overwhelming anyways, so I don't worry about programming in a set rest day, as life tends to get in the way enough as it is.
I hope that helps. Good luck on your journey!
“Whatever you hold in your mind will tend to occur in your life. If you continue to believe as you have always believed, you will continue to act as you have always acted. If you continue to act as you have always acted, you will continue to get what you have always gotten. If you want different results in your life or your work, all you have to do is change your mind.” Unknown
"Strong people are harder to kill than weak people and more useful in general." - Mark Rippetoe