Hey Zoe,
As soon as I was back from the hospital, I used four pillows to sleep. My bed is up against the wall which also provided some support and stopped the pillows from shifting.
I stacked two pillows and placed them against the wall and the other two against my headboard making an L and right angle.
I slept right in the middle of that, it kept my back elevated and didn’t leave all my weight on my tailbone. Also meant that heat and ice packs didn’t roll all over the place!
I hope you find a way to get cozy
x