DAE experience very frequent irregular heart rhthym?

For the past 4-5 days, I've been experiencing near constant palpitations (think one every few seconds to every few minutes). I went to a doctor; an ECG revealed that my heart rate was jumping between 55 to 65 bpm, causing the 'skipped beat' sensation. Blood test results will reveal whether or not I have a thyroid problem, but other than that the doctor seemed to think it was anxiety related, and nothing I should be too worried about. However, I feel like SHIT. I feel like I can't do anything because the harder my heart works the more strongly I feel the palpitations. Throughout my anxiety I've worked hard to not avoid the things I enjoy, like going to the barn or going on hikes. But now I've been staying away from anything that involves physical exertion, because I hate/ am scared of the feeling of palpitations. Any advice or commiseration?