Struggling to get over block in visiting GP services

Hi there, 

Apologies if this has been covered already - I figure its not a too unfamiliar exception that some additional views couldn't hurt. Don't feel obliged to answer all of the questions. TIA

Getting to the point - I am writing to see if any ND/Autistic folks have been able to use something like an advocate for when you want to visit the GP, arrange appointments? 

First Question: I am recently late diagnosed Autistic womxn, and so unsure what support is available. Unsure if it is better to try and recruit a friend as a advocate while visiting GP. (Not entirely sure how possible that will be for me.)

Personally, I struggle just to book an appointment, probably based off of years of painful interactions and dismissals, that either felt like I was being gaslit about potential issues, or like I was trying to fit a square peg in a round hole. (couldn't think of a better analogy.

One of the last experiences I had, the GP said I needed to forget about having previously been diagnosed a Hormonal Disorder in relation to pelvic pain- despite it being something that can develop into further complications if untreated...

I know this isn't an uncommon experience, but it's got to the point I feel I have too many potential issue's I should visit the GP about, I do not know where to start. 

Things around not breathing well, also loss of smell, (followed by appetite for around a year)

Severe fatigue 

Constantly feeling unwell

To me, if feels it makes sense to mention these things together, but its possible, because I have scripted beforehand, I do not feel I have said all I needed to say, and get caught off gaurd by random questions from the GP.

Second Question: How can I, as a younger woman with a mostly disguised presentation of Autism, advocate for myself, or speak to the surgery about this issue, as I know as I get older, it could be even more important. - It took me 2-3 years to build up the courage to suggest to a GP I think I am Autistic, just as an idea of where I am at. 

Last question: What solutions, techniques have other folks tried with some success?

Thank you in advance for reading. 

Crys