I always bring someone with me who is willing to speak up. I can barely speak for myself so it's hard to advocate but I write down what's bothering me and have them speak

I've found it really helpful to write down everything before I go. On paper, if I know it's going to be a problem, or on a notes app on my phone, if I think I may need to refer to it or i have a question i don't want to forget to ask. This helps me organize my thoughts, prepare mentally for the visit, and I think it has helped doctors take me a little more seriously.

Honestly? Don't. Just walk away, you have no obligation to explain yourself to a doctor who's doing nothing but wasting your time and dismissing you. If that's not an option, phrase your protests as questions, ask for clarification on the stuff you know is wrong

Make sure they chart everything. They turn you away, refuse to run a test, or deny any treatment it better be in the chart.