I worked night shift for 1+ years in the OR. Just like working on a floor or nursing home, the OR, ED, etc, all have slow and crazy times. If the OR was crazy, the time flew and my shift was over before I knew it. My patient laying on the table was more important than getting some shut-eye. My patients' are putting their life and trust in my hands. It's a HUGE responsibility and not something to take lightly.
When I had slow nights, I stayed active on my feet and did everything (in addition to my regular duties) from cleaning, organizing, stocking, and even exercising. I brought my tablet with workouts I could stream. I drank more water (more water= more bathroom breaks) when I saw my coworkers scarfing down sugar-laced foods and coffee to stay awake. My rooms were checked and double checked to make sure my day-time coworkers had everything needed for that case. I got any certifications/continuing hour educations worked on when the opportunity rose.
Was it easy? No. I was lucky if I even got 4 hours of sleep before my shift showed up. Come morning, I was dragging, but I never fell asleep. The facilities I've worked at (like most others) have a no-tolerance policy for sleeping on the job. By doing so, you put your patients' safety at a huge risk. If there's an emergency, your co-workers will not have the time to find you and joustle you awake. If one of your patients' fell and broke a bone or got a subdural hemorrhage that requires an emergency craniotomy, how would you explain not answering the bed alarm? "Oh, I was asleep and didn't hear it go off?" Another example...your patient has an emergent GI bleed that requires stat treatment, but declined due to not being treated quickly enough. Falling asleep will not hold up in a court of law. Night shift has less resources due to decreased staffing. It is imperative to be awake should an emergency rise.
OP, you may need to take a look at your schedule to see how to organize things to get some sleep. Plenty of people I know also take sleep aids (prescribed or OTC like melatonin). It is worth a try. Good luck.