I would ask for some blood work to check for vitamin levels and mineral levels, you could be low in some of the important ones. Also, maybe ask to be tested for Fibromyalgia.
Go to your local hospital if you are worried, doctors are human and get things wrong from time to time. The A & E will see you, just tell them everything. Good luck, and I hope you get you health back soon.
You might want to get blood work testing for Vitamin D, Vitamin B12 & magnesium.
Magnesium relaxes the muscles and can lower heart rate.
Vitamin and Mineral deficiencies can make you feel all your symptoms.