What is buried deep down in your muscles, your bones, that is ready to be released? Perhaps much much more than you realize.
Your body indeed stores all kinds of energy in the muscles of the body; I know this through my Vipassana meditation practice. The good news is that calming the mind allows this stored “pain/stress/whatever you wish to name it” to be released, leaving your new self lighter and more at peace than ever.
I find it similar to what happens when you clean up your diet, at times, the body actually feels worse initially, because as your body becomes clean, there is a chance to release the stored toxins that the body stores, which it does apparently so as to not overload the liver and kidneys at any one time.
In order to start this cleansing process, you must learn how to listen to the body, and that starts with calming the mind of all the noise, and tuning in to each part of the body in turn.
I strongly recommend attending a 10-day Vipassana retreat if the idea of releasing and letting go of your pain sounds interesting.