I don’t know if this will help, but I’ve had doctors recommend following organizations like Dysautonomia International or the EDS Society since they’re good resources for patients and physicians. If it’s a comorbidity, maybe you could find something they published that you could bring to your doctor?

That is a valid worry that a lot of us go through. Honestly I've been to countless doctors who roll their eyes at me when I start speaking in medical terms, and write me off as "just having anxiety". Recently I went to one I was super nervous about bc of past experiences and he actually listened and even asked if I was a nurse because I was so knowledgable. I enjoyed the interaction bc he actually respected me, and we are still working together to get to the bottom of things. (He even asked consent before physical examination, you dont find them like that often!) Google is not all bad. I have learned invaluable information from it. Keep doing you and keep looking into your own body because nobody knows it better than you.