I had rheumatic fever as a child (1960) but don't know if there are differences in how the disease effects children or adults. I remember all too well some of the symptoms you mention like the aching joints and not having any energy. I had a heart murmur as a child but it hasn't been heard for at least 20 years. I was on once a month Bicyllin from age 6 - 25. I became a medical technologist, partly because of the testing that I had to have done back then. Do you know if they ran an ASO titer or Sed Rate on you? When I was still a med tech, those were standard tests for suspected rheumatic fever.
You may want to check out the following link. I've copied in a section about rheumatic heart disease:
"Rheumatic heart disease. During a first rheumatic fever attack, about half of people develop heart inflammation, but this doesn't always result in permanent damage. Most people with rheumatic fever recover fully after six weeks. In some cases, however, one or more of the heart's valves may be scarred. Permanent heart damage due to rheumatic fever is known as rheumatic heart disease. In many cases, heart damage isn't discovered until years later."
ask your doctor for a blood culture test. Rule out bacterial infection or indocardio...