Comment by bane
Every woman I know who's been properly diagnosed with endo had to self-diagnose first, and then advocate to be tested. Not a single one was properly diagnosed by their doctor first. I'm not sure what the reason is, even women who go to doctors who specialize in endo seem to miss it unless the patient self-identifies.
The path to figuring it can be long and sometimes improbably. For example, somebody I know was watching a youtube channel they like, and one of the creators put out a side-video about a short informational cartoon they made about their own journey discovering they had endometriosis -- which also echoed this same diagnostic pattern.
My friend saw something in the cartoon that seemed familiar, decided to go get a biopsy, and voila - a lifetime of pain was finally answered. She was in her late 40s, and decided to just go get surgery and now a few years and a hysterectomy later lives pain free.