What can be causing tightness in my chest and pain in my lower back?
It is usually caused by a strain of the muscles of the ribs and chest muscles in addition to the spine and back. The chest discomfort may be caused by asthma or unlikely, a heart problem. Pulmonary function test and a possible "regular" effort should be checked to help make the diagnosis. See your doctor will help you with this. Physical therapy and yoga may also help you.