Prementrual Syndrome- it could happen to YOU
i've known girls who've had good results with raspberry leaf as a remedy for cramps, and maybe other menstrual-related pains. i think it works best if you start drinking a (strong?) tea of it as soon they begin, or begin to begin. also it's pretty cheap; get it in the bulk section of yer local health food store.
wild yam is another one i heard a lot about, which i think is also good for cramps. i believe it also is generally good for tension, which would probably help your back pains. i think the root is used, maybe the whole plant too. (maybe the root is most potent.) i know it grows all over the east coast, i dont know about other parts of the u.s., but probably. but at any rate, i haven't heard as many personal testimonies about wild yam as raspberry leaf.
there's also this stuff called "cramp bark", a native plant, but i don't know anything about it, except that natives used it for general menstrual pains.
peppermint leaf would probably help with the pains, because it relieves muscle tension. a lot of plants relax the muscles... cheap ones like lemon balm, chamomile... others like skullcap (i dunno how much it is), kava (probably more expensive?), valerian (expensive also? not sure)...
also massages can help with the back, if'n you can coax someone into massaging you.
i learned a lot about plants in asheville... big herbal health/wild plant scene there. raspberry leaf seemed the most popular choice for menstrual stuff.