endometriosis?

I've been experiencing such intense pain with my last few periods and this week have been so bad that I cannot talk in full sentences and it doesn't just come and go it's constant! I've taken tramadol and it hasn't taken any effect on the pain,
And it is a significantly heavier flow than normal. I've been having to change products at least every hour, and I'm so bloated I look about 5 months pregnant!!
My sister told me about endometriosis and said I should go to the GP but I'm so worried about the doctor telling me to just "get on with it" 
Has anyone else experienced this? What did you do? 
Thank you xx