u/frailFalcon345

My current (hand-me-down) mattress is way too firm for me that I’ve been waking up with sore hips and stiff shoulders almost every morning and this has been going on for almost 3 weeks already.

I want to replace it asap because I don’t want to put up with this anymore. Any idea on what’s best for side sleeping (sometimes back)? How do I know or identify which one’s right for me??