I have had severe pain with mine since I was 9 when I got it initially. Cramp bark tea is my remedy of choice, it effectively relieves the pain naturally, but it really tastes horribly bitter. I recommend adding honey and perhaps a regular bag of rooiboos or a berry tea to help improve the flavor.
As far as emmenagogues are concerned, (these are herbs that bring on periods) I know that celery seed, angelica, parsley, yarrow, feverfew, rosemary, sage, Queen Anne's Lace seeds, blue cohosh, black cohosh, mugwort, juniper, rue and Vitamin C work for this purpose.