Working nights or shifts, will always send your body clock haywire.
I had nearly 35 years of it, constant changes of sleeping times.
I actually did think that it was the shift working that gave me my weird sleeping habits, but it was my condition.
You will find, that as above have said that once you have control of your diabetes, then your energy levels will change and the likelihood of hypos become less.
Always carry something with you as a quick boost to your levels if you feel wobbly at any time. The longer you low carb the more you won't need them.
Eat regularly and always keep busy, stress and worry will not help.
I believe if you can get your control and your Hba1c levels improve, there will be no reason why you can't go back to being on call.