Bests & Worsts Reviews from Amazon

I read the reviews before making my decision and since so many were positive I went ahead and bought a full. Of course the price dropped shortly after I did. I was expecting comfort and padding, I'm thin so maybe that's why I wake up sore and with red spots on my side. I'm so upset over this and in pain every morning, my chronic back pain is worse than ever. My arms and hands fall asleep during the night every night. It's horrible and so uncomfortable I can't believe there's no way to return this. I get into one position and stay in it all night because all I want to do is sleep and I wake up in pain. I've only had it 6 days but knew after the first night I'd made a horrible choice. I wanted a new bed for my new apt I moved to on 8/9/18 and had this sitting in a box for a few weeks before my move, looking forward to using it. Now it's all I can do to try to sleep at night knowing I'm stuck with this discomfort and it's not possible for me to buy another better quality mattress. (Disabled and only get social security). I even wrote the manufacturer several times before making my purchase and asked them questions re: comfort. I was concerned but they reassured me it would be fine. It's not fine--worst mattress I've ever had!