I could go on and on about this topic and my own personal hypotheses about menstrual cycles and hormones, but I'm no doctor so I'll spare you my unproven theories. All I know for sure is that about a year ago my husband got a vasectomy, so I stopped taking birth control pills, and started getting PMS. It seems like every month the PMS gets a little worse. With my last period, the PMS started about 2 1/2 weeks before my period started and was more intense than it's ever been.
I started looking online for solutions. Everybody wants to dope you up: birth control pills and anti-depressants were the most-used solutions. But I kept looking for an alternative because I don't like the side effects that come with birth control pills and anti-depressants. There are a number of vitamins and supplements you can take, including B3, B6, D, magnesium, and St Johns Wort. But the one that sounded most promising to me is L-tryptophan. I went to the doc's office yesterday to talk about my PMS. He of course immediately suggested an antidepressant, but I told him I didn't want to go there and then mentioned the tryptophan. He said that sounded like an excellent idea. I actually went to see him because I hoped he could give me a prescription for tryptophan so my insurance would cover it, but he said it's not available by prescription. So I picked up a bottle yesterday at a vitamin store and took the first pill last night. Hopefully I'll avoid a PMS episode like last month's! I was the same as you; I hardly knew myself and couldn't stand me.
I wish I had saved the website I found that really described how and why the tryptophan works. But I would encourage you to do your own research on it. Best of luck!