The key head and neck issue is to not relax the neck in a posture that puts strain on the joint. If you lay on your side, your spine should be straight.

I usually sleep on my back with no lift from my pillow. It just supports the side of my head so my head does not roll to the side. It I sleep on my side, a bunch up my pillow so my head is supported so it does not drop to the side or be tilted up.

The laying on your side with your head supported by your hand and elbow sounds like it puts side tension on your neck. It does not sound good to me.

I learned this when I was having an EEG with a sleep session. I stayed up all night so I could sleep during the EEG. The tech rolled a towel and put it under my head to prop my head up with my chin toward my chest so the wires were not disturbed. After some tests, I was told to relax and go to sleep. As I tried that last bit of relaxing where I relax my breathing, I would get short of breath. A few cycles of this and I realized that when I relaxed, my diaphragm stopped pulling breaths. I could not sleep in this position because I would stop breathing and gasp.

I tried this posture at home and realized this head forward posture, after about 5 to 10 minutes, was interrupting my breathing triggering system. This is known as Central Apnea. If I tried to sleep with a thick pillow, I would do it at night. 16 times in one hour when my wife stayed up and watched. Even when my breathing was not interrupted, I would wake up feeling miserable after having a night of stressful dreams. It would be what we came to call a 'no driving day.' because I would be so foggy.

Once I learned to avoid these postures, my recovery progressed substantially. My neck is much more stable but I still need to be careful.

A PT and a chiro did gentle traction and mobilization to help the joints stay mobile. No pushing for range of motion.