My lower back hurts when i breath in..why does it hurt? i also feel like i can't breath at times like its hard for me to breath.. shortness of breath

?: Assuming you have not been subject to trauma, there are 2 internal organs in your back that move with respiration: your kidney and your lungs. Since you're short of breath, we'll presume it's the latter. If you have fever, cough, and phlegm, you likely have pneumonia. If you don't, you may have pleurisy (inflamed lining of the lung). You really should be evaluated/examined. Pls see your doc in am.