I'm a nurse too, and I have been able to make it through the 12 hour shifts while on the master cleanse. But I do agree that every body and every cleanse is different. I would advise you to be sure to have plenty of lemonade on hand; it really helps when you're feeling a little lethargic. It might also be helpful to have some extra maple syrup to add even if you end up going over the allotted amount. That's better than having to quit the cleanse, right? I have found my energy and mood to be pretty high with this cleanse. I think it's good that you started today; by tonight you should have a pretty good idea of some possible side effects like headaches etc. From all of the postings on this site, I have heard that it is absolutely necessary to slowly work solid foods back into the diet, BUT I went from a 14 day master cleanse straight to eating pineapple followed by a full meal a couple of hours later with no ill effects. I wouldn't recommend it though as I've heard horror stories. Good luck with everything, and keep coming back here for support!