Stress and anxiety can tighten your muscles without you even realizing. I love that I have an outlet in#piyo to release those muscles through stretch, and body weight strength.
If you don’t have a class, take time to stretch at home. A simple Down Dog, Up Dog, Pigeon, or runner’s lunge stretch can open your body and release those stressors/tightness your body is holding on to. You may not be good at it at first, it might be hard, it might hurt, but it should be a “hurt so good” feeling.