You could probably try one of those memory foam mattresses or pillows (the type that take the shape of the person using it). I would also recommend not changing your sleeping habits because everyone's body is different, and so they go to sleep different than others do. Not everyone goes to sleep on their back; I like going to sleep on my side or my stomach. Sometimes, I think that the floor is better than my bed, except that causes me to be sore in the morning if I sleep on my arm or shoulder. It's just because I like to sleep in a cooler area rather than a warmer area.
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I'm 24 years old and live in WA State. I was diagnosed with Asperger's at 9. I received a BS in Psychology in 2011 and I intend to help people with Autistic Spectrum Disorders, either through research, application, or both. On the ?Pursuit of Aspieness?.