Our friend had a similar story to yours, they were told they were making it up despite the fact they were starting to die anytime they went out in the sun, it took multiple near death experiences for them to get diagnosed as a child. I've never run into anyone else with it in the UK but there is a community of expats with it in Rotterdam the Netherlands as they have one of the best Porphyria treatment and research centers in the world. Our friend emigration their a while ago for it and has been using the new implant that's been developed and they've said it's completely life changing - it doubles their exposure time and allows them to live a much more normal life. If you'd like to make contact with other people with it, feel free to DM me your email and I can pass it along.