When I realised my pain was 10 times worse than labour/child birth I KNEW that it was something more than period pains. My GP (female) said straightaway that it was endo and explained it all to me (I HADNT heard of it before).
Was referred immediately to a gyno ... all good so I thought, BUT THIS IS WHERE IT FAILED ME.
The gyno was a "GENERAL" Gyno who saw me (in fact specialises in teenage pregnancy and c sections!!!), quick scan then booked me in for a lap 2 weeks later. Was told after the lap yes you have endo and a small cyst on your ovary but Ive had a good fumble around whilst I was in there plus a bit of releasing of old scare tissue from an appendix operation from 30 years ago so all should be fine.
I was so relieved and delighted that I was "sorted" BUT 6 weeks later pain came back just as before in fact worse. I was at work and nearly passed out, came on so suddenly and within 2-3 mins the pain was at its height. I was so angry 
So I got to the internet and did my own research, time and time again it came back that YOU MUST, MUST BE REFERRED TO SOMEONE WHO UNDERSTAND AND IN FACT SPECIALISES IN ENDOMETRIOSIS.
So I did, I found a private consultant who luckily also had an NHS clinic, so I rang his Secretary who told me what NHS slots he had free. Armed with the information I went back to my GP and insisted I get booked in there and then. Ive been seeing him for 3 years now, and am managing my pain, also found out the miscarriage I had and long time to conceive again was most probably down to Endo. (So blessed to have my one and only now). I am now down to an annual scan and visit now to monitor what's going on.
My advice would be to research your own local consultant, dont get fobbed off, insistant you get referred to who YOU want to see.