Incorporate some more leafy greens, that always helps with the bathroom. Also be sure you're drinking enough water, water is -extremely- important in elimination. First thing in the morning, right after waking, have at least 8-12oz of water, room temp is best. Just chug it down. That should help get things moving as our bodies are normally ready to do some business after a nights rest and digestion.
For you cycle, any change in diet has an effect on your hormone levels thus effecting your period. If you were coming off a hardcore SAD your bodies hormone levels are probably stabilizing and working out how to operate with out interference from added chemicals/sugars/hormones etc. Give you body time to adjust. If you were average weight and have lost weight that might also be the key. If you were over weight and are losing weight, again, your hormone levels change in the process thus disrupting your cycle. I'm not a doctor, or even all that smart, so don't take any of this information too seriously, I just know what I've been through personally. If you don't start in the next month or so maybe you should see your doctor to make sure nothing is amiss. Nobody likes stirrups. But sometimes, we just gotta climb up and spread to make sure everything's okay!
"It is not what you are that holds you back, it is what you think you're not."