Hi, Based on the history you have shared, if EKG and endoscopy are normal two big causes of such symptoms are effectively ruled out however for reassurance echocardiogram must be done to rule out any structural heart disease symptoms or aortic dissection etc however these are very rare causes. It is better to get a baseline thryoid profile as well serum electrolytes and to rule out endocrine causes which again are very rare specially conditions like pheochromocytoma or carcinoid and are least likely to be causing but may be needed to be ruled out. It can be neuromuscular pain altogether and X-ray cervical spine to rule out cervical spondylosis must be done. A chest X-ray for any signs of any lesion causing autonomic nervous system involvement should be ruled out. Wishing you a speedy recovery. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Saddiq Ulabidin, General & Family Physician