Visco Elastic Foam Mattress

Lately my fiance has been complaining about her back hurting when she sleeps on our bed. So being the curious individual I am and being my side of the bed so unbelievably comfy we switched sides for a night. When waking up in the morning my back is in some sicking pain towards the top of my shoulder blades and it feels like my sinus are rather heavy almost like I am laying with my feet above my head.
I got out the level and check the frame and then laid a heavy book on top of that side of the bed and checked the level of the bed and everything is more or less perfect.
So my question is what would cause something like this and how would we go about fixing it without spending too much money.
Notes: Our bed it made up of 4″ of memory foam onto then springs on the bellow that, it is a CalKing, and sits on two separate box mattresses.
any help would be greatly appreciated
Thanks!

For the past siz months – year I have been waking up with terribly tense shoulders, neck, and upper back.
I sleep on a queen sized mattress which is directly on the floor of my room (no bed frame, no box spring). Could this cause muscle pain?
I sleep with one pillow, although I have a memory foam special neck pillow that I use when I just can’t stand my normal pillow.. I have to say that the special neck pillow really doesn’t make any difference at all!
I notice I do tend to “shrug” my shoulders and squish tightly to my pillow… no matter how hard I try, that is simply how I fall asleep.
Do you think all, or any of these factors are the cause of my muscle pain, and does anyone have any suggestions of what I can do to relieve it?

I have chronic neck pain from several car accidents. The doctors can’t find anything official wrong, and pain meds don’t help. The pain got a little better after physical therapy. And it’s now been about 2 years, but the pain is still there. This week it’s gotten worse. Especially during sleep. I bought an expensive tempurpedic pillow, but I hate it. It was too hard the first month, ok the second, and now this third month is horrible. It does not support my neck because the memory foam squishes down too much. Also I’ve seen the chiropractor a good one, many times, it’s very temporary relief.
So questions:
1. If you have a similar situation, do you have any suggestions for pain management?
2. Can you please tell me a better pillow? That will continue to hold support. (my mattress is fine)
Please help, it’s started to give me such bad pain that I’m also developing painful migraines. And meds aren’t helping that either.

Because of temperature difference between the back and the mattress, there is no pores for the moisturised air to get released.

i purchased a memory foam pillow, as a trial period, and although its still as hard as rock i have to say its still kept its shape, my thoughts are now would the purchase of a mattress with memory foam, perform the same way ?