Hello thanks for asking from HCM

The accelerated heart rate, stiff body could be due to anxiety. Anxiety results in rapid heart rate, palpitations, tightness of shoulders, chocking sensation in throat, tremors etc symptoms. But if the pain is increasing on breath then that is due to some muscular origins. This can't be labelled due to anxiety.

I'd advise you to visit a psychiatrist for evaluation. Drugs like SSRIs like Fluoxetine, Paroxetine, Sertraline etc are used commonly in anxiety and have great efficacy. You can visit a psychiatrist for opinion and prescription.

Thanks and Take Care

Dear user
Welcome to HCM
We understand your concerns
I went through your details. PANIC ATTACK a sudden overwhelming feeling of acute and disabling anxiety. Panic disorder is different from the normal fear and anxiety reactions to stressful events. Panic disorder is a serious condition that strikes without reason or warning. Symptoms of panic disorder include sudden attacks of fear and nervousness, as well as physical symptoms such as sweating and a racing heart. Panic attack always happens due to an underlying anxiety disorder. So you need to treat anxiety disorder. Anxiety disorder is treated with the help of counseling and psychotherapy. You should consult a psychologist.
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Hope this answers your query. Available for further clarifications.
Good luck.