Hi, I used to suffer from bad cramps and extreme moodiness. It runs in my family. I have been taking a multivitamin w/ iron called Isotonix Multivitamin (Multitech is the old name) for years now. It is predigested so you absorb more of the vitamins and minerals than regular vitamins sold at the drug store. Pills and other forms of vitamins take 30 minutes sometimes to be absorbed and then your body usually doesn't absorb all of it...that's why usually your urine is darker afterward (because you're excreting the stuff that wasn't absorbed). This is absorbed in 5 minutes.
When my husband suggested I take it because I'm a vegetarian I resisted but I decided to try it. Well, for months afterward I didn't even know I was getting my cycle until it came. I didn't know why but I was thrilled..no more screaming at people, feeling like I wanted to crawl into a ball and die, etc. After a few months, it dawned on me that it might be the multivitamin but I wasn't sure. I also didn't want to admit to my husband that it was helping me ;) but it was confirmed when I ran out of it one time and got a bad case of PMS. I was miserable again...haven't missed a day since! I still get some minor weepies here and there but the weepies I can deal with...feeling awful, miserable, moody, crampy, and angry at the world I don't like. I hope you find something that helps. If you'd like to try the Isotonix Multivitamin go to www.shopyed.com and click on Health & Nutrition and then General Health (in the window that pops up). Or you could probably just search for it.
Don't forget to get the one w/ iron. Women need the iron, men don't that's why there are two different ones. I hope you are feeling better soon...I remember what it felt like and I don't envy you.