You really need to check with your doctor for a proper diagnosis for this one, as it may be something like a problem with your pancreas, which can manifest as referred pain in the upper left area of the back.
Explain to the doctor how severe the pain is and how long you have had it for, and that it isn’t helped by the usual pain remedies – this will make it clear to the doctor that there may be a more fundamental underlying cause, rather than just a muscular issue.
It is also possible that the muscles between your ribs in this area of your back have become inflamed (a condition called costochondritis), and your doctor can easily check for this by locating a particular tender spot.
Do you have questions? Please feel free to ask.
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