Hello, Welcome to Just Answer and thanks for your question. What has your primary physician had to say about the pain?
That is what I was thinking as well. Has he provided a referral to a psychologist or psychiatrist for treatment? That would be the best plan. Anxiety can cause muscles to tense up or spasm leading to pain. Heat can help reduce the pain, but treating the cause of the pain is always the best plan. A psychologist can help you with talk therapy and exercises to help you deal with stress so you don't become overwhelmed. A psychiatrist can prescribe medication if the anxiety is bad enough to interfere with your lifestyle.
Absolutely not. Ten trips to the ER that ruled out anything cardiac are more than conclusive. In fact, two would have been sufficient.