Hello there I have read through your question and understand your concern. Tightness in chest and back along with difficulty in breathing can be due to muscle spasm or intercostal muscle strain which is a self resolving condition. It can be relieved by rest, light stretching exercises and antiinflammatory like advil. But these symptoms can also be an indication of a more serious condition like angina. I would advise you to get yourself assessed by your physician for proper assessment. He may advise an EKG to diagnose any underlying cardiac causes. I hope that answers your question. If you have any further questions please feel free to write. Thank you for choosing healthcare magic.