Hi pmsmith2032,
Subject to first confirming that any retailer or manufacturer on the list that you wish to visit is completely transparent (see this article) and to making sure that any mattress you are considering meets your criteria and the quality/value guidelines here … the better options or possibilities I’m aware of in and around the Chicago, IL area are listed in posts #2 and #4 here.
I would certainly suggest including My Green Mattress/Quality Sleep in your research if you are in the area.
While it’s not possible to “diagnose” mattress comfort issues on a forum with any certainty because they can be very complex and there are too many unique unknowns, variables, and complexities involved that can affect how each person sleeps on a mattress in terms of “comfort”, firmness, and PPP or any “symptoms” they experience … there is more about the most common symptoms that people may experience when they sleep on a mattress and the most likely (although not the only) reasons for them in post #2 here (at least to the degree that any symptoms are the result of a mattress and not the result of any pre existing issues or circumstances).
While I can’t know for certain … it’s possible that your discomfort could be the result of a pillow issue because one of the most common causes for neck and shoulder issues is the pillow you are using. A suitable pillow is an essential part of good alignment for the head and neck and upper body and can reduce some of the pressure on your shoulders (which can lead to tingling in your shoulders and arms) because the gap between the head and the mattress and the curve of the cervical spine needs to be supported just like all other parts of the spine. Like mattresses … there are certain “needs” that depend on body type and sleeping positions but with pillows, personal preferences play a more important role because the face is much more sensitive to textures, temperature, smells, and other more subjective “feel” based properties of a pillow. There is more about choosing pillows in the main pillow topic here.
The other possibility that is more likely is that the upper layers of your mattress have softened under the shoulders and are no longer isolating you enough from the firmer layers underneath them. It’s also possible that foam softening under your shoulders has led to some type of compensation or “adjustment” in your sleeping position that has resulted in sleeping with your shoulders out of their neutral alignment which can also restrict blood flow and cause “tingling” in your shoulders and arms.
Phoenix