Magnesium (glycinate) definitely helps. I was taking it before my doc even prescribed. Helps with muscle cramps and better sleep etc. Dunno about what you get where you are, but aim for atleast 320 mg daily if you get some capsule supplement.
Someone who has endometriosis as well actually recommended this to me, and I was hesitant at first, but Flo vitamins have helped me with my bloating.