What Causes Fluctuating Heart Rate,low BP And Labored Breathing?

In 2012, I had an ablation and two cardioversions. Since then, I have had no A-Fib symptons, until now. I am stressed out with being a caregiver for my husband who suffers from Alzheimer s, diabetes, COPD, post polio problems in his legs. Last week, I entertained company from California for a week. I had a party for my husband s 84th birthday with 16 attending. Then the following Thursday, before they left for home, they wanted me to serve dinner again before leaving. I, too, am 84. I know I overdid, but I felt it was my duty. I am so tired, pulse fluctuates from 60 to 114, and my low BP has been 89/48. I feel as though I am dying. My chest is heavy from osteoporosis, making a sick feeling in my stomach and chest area. My back aches. I have no strength in my trunk area, walk bent over, and I have no strength in my legs from knees to feet. I walk as though I am drunk, My breathing is labored. I would rather sit or lie down than stand and walk. I am currently hooked up to a 48 hr. holter monitor and will get results next week. Are these symptoms of MD, or similar diseases? I am taking amiodarone, metoprolol, evista. lisinopril, omeprazole and vitamins D & C along with Citracal and 81mg aspirin. Please advise. I am currently under the care of a cardiologist, GP, urologist, dermatologist, and more. All I want is to feel better, and shed this sick feeling. It feels similar to pregnancy symptoms. Thank you.