Brief Answer:
Heart or lung problems possible.

Detailed Answer:
Hello. I read your question carefully and I am sorry about the symptoms you are experiencing.

Most of your symptoms could be explained by a heart condition with failure to bring enough blood to head and extremities, which could cause most of the symptoms you are reporting.

The causes can be several, if it has began abruptly although not typical for your age myocardial infarction could be the cause. If more gradual then heart abnormal rhythm (to be suspected with your thyroid problems history), heart valve or muscle disease.

I suggest you be evaluated by a cardiologist because physical exam and tests are needed, both to exclude other potential diagnosis (pulmonary embolism) as well as to identify the cause and receive appropriate treatment as it could be a serious condition. The prognosis would depend from the cause and degree of damage, but it usually is treatable.

The back pain could also be in the setting of the scoliosis in your medical history.

Anxiety issues could also present similarly sometimes, but that should be considered and dealt with only after an evaluation and exclusion of heart and lung issues.

Feel free to ask further questions but if possible with more detail on the evolution of the symptoms like: when did they appear, which symptoms first, progression in time, chest pain location, intensity, character (pressuring, tightening, squeezing, sharp, discomfort etc).

Hope things work out for the best.

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