Has anyone been misdiagnosed with fibromyalgia?

Three years ago I got diagnosed with fibromyalgia. A year after I noticed my heart rate would be high and I went to my doctor and suspected POTS. They did a holter monitor and put me on a calcium channel blocker and nothing changed. I couldn’t see my doctor for over a year. The rheumatologist I kept seeing just kept saying “it’s just fibromyalgia. Just workout and eat lots of greens and stay hydrated” which I already did. I moved to a different state and mentioned I thought I had pots and the doctor said they did lots of testing for pots since it was really common. I got tested for it and I found out I had orthostatic hypotension instead. I got put on a beta blocker and I’ve never felt better in my life.