thank you for the question.
Your pain is less likely to be due to a heart condition. A heart condition would have caused an intermittent pain that will last around 2 to 10 minutes. It will not cause a constant long lasting pain. A heart condition will cause a pain that increases on physical activity, and this pain will radiate to the neck, jaw, and arms. So, your pain is not typical of a heart condition. Also a heart problem will cause associated symptoms such as shortness of breath, nausea, vomiting, increased heart rate, dizziness, profuse sweating, belching, and awareness of heart beat. In absence of these symptoms a heart type of pain is unlikely.
So, I do think that your pain is likely to be a muscular pain, or due to costochondritis, or related to anxiety. You should have an electrocardiogram done to rule out any obvious heart condition. A normal electrocardiogram will also give you peace of mind, and make you more certain that this is not heart related.
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