Fluctuation of calories burned and calories eaten

So I work a very active job over night and typically end up with a day that goes from 7am to 5 or 6 am the next day. I find I don't eat "extra" before the work shift or even necessarily the "day after" when I get up 5-6 hours later but the following day I really eat alot. E.g. Saturday night I worked, I ate about my daily intake of just under 1300 calories. I earned well over 1200 from activities. Sunday I got to sleep for a heavenly 10 hours (completely unheard of) and then only ate one meal before heading back to bed for a fabulous 8 hours of sleep but lo Monday rolls around and suddenly I'm 1k+ over my daily... does anyone else run into this ebb and flow of calories? Is it fairly natural for my body to want the extra calories later? I'm also craving a good hard cardio workout, my pilates class last night was merely an appetizer. Anyways just curious how the rest of you handle your roller coasters... Thanks!