It's a pretty complex illness with a whole bunch of symptoms
likely to happen. There are many causes of fatigue
and unrestorative sleep and your doctor should check you for them, to name a couple, thryoid function (low or hashimtos), sleep dysfunction (apnea, non-rem). Your work schedule itself may be confusing your body. If you can't switch to a different routine, something that might help is melatonin found at a health food/vitamin store.