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What causes your pain? If it's a back problem (disc or joint), you can also try this: https://www.amazon.com/Innotech-PropAir-Sleeper-Back-Pillow/dp/B01LYGC4WW/ref=sr_1_1?ie=UTF8&qid=1517696932&sr=8-1&keywords=PropAir
A pillow between knee as other suggest is also good for your hip too.
I have a new bout of pain with sleep, but there are are few tools I use to keep the pain at bay. Definitely check out your mattress and move sleep positions to find a firmer spot. If it’s sunken in, your back is likely in flexion all night causing your pain in morning. I use this back pillow under my lumbar for support throughout the night. It’s awesome and adjustable with an air bladder. I also use a wedge pillow similar to this one, but mine is extra long so my feet don’t dangle down (causing nerve pain). It’s good to have a couple tools at your disposal because I find one may work for months and then I’m experiencing pain again and a different one will work.