I have severe upper back pain.  Feels like someone clenching their fist in it and digging nails in it.  Will be moderate for a bit, and then will tighten again and be painful.  Radiates to front chest pain (chest just has mild to moderate pain) radiates to neck, which is mild, Shortness of breathe, extreme fatigue.  I have had mild symptoms for three weeks.  Intensity is getting stronger and more painful.  Is this a heart attack.  How long do heart attacks last.  Should I wait and go to clinic tomorrow.
I have gone through the details provided by you. Let me assure you that this is not a case of heart attack. Your upper back pain is occurring due to muscle spasm. The muscles sometime go into spasm and remain contracted in the process giving rise to fatigue and pain. I would insist you to take some muscle relaxant like MySpace forte twice a day for a couple of days and see if you get some relief. Hot compress alternating with cold compress should help in reducing the pain. You should definitely go to the clinic tomorrow. It might still be worthwhile to remain in the follow-up of a doctor who can examine you and tell if there are any other possibilities to consider and can intervene accordingly.