Dear Miss Giver, I left nursing after working as an ICU nurse for 27 years, Back to school to be a Physician. Best decision i made. We have a greater knowledge of the effects of Shiftwork on our body. There is a serious disruption of Melatonin and Cortisol which regulate the Circadian Rhythm. You may need a leave, rejuvenate and come back with a clear mind where opportunity has a place to land.