If you're struggling to find the perfect balance between softness and firmness for your needs, it may be time to switch mattresses. The following are 4 signs that indicate an overly-soft mattress:1: You wake up with stiff back pain or sore shoulders2: After getting into bed, it takes time to settle in. ( you feel uncomfortable)3: You sleep on your stomach and frequently experience neck or shoulder aches when you wake up.4: Getting in and out of bed is difficult for you.