I think u r getting tearing sound in ur lower back.. its bcoz of work stress and in activity or poor posture.. some times its hapaned who is started exercises after some of periods.. so it is common nothing to worry about that. Bt now u should do only stretching and free exercises.. dont go for strengthening exercises and weight bearing still minimum 15 days starting periods of work out.. u should maintain ur posture smart.. now its not serious problame bt if u r getting any other indication like pain, tingling sensation, numbness and tenderness then u should consult with ortho dr.. Thanks.. TC