Not getting a period!!

So I've been on vitex for almost a month now. First few weeks got me all bloated everywhere and acne went crazy all over my face. And now it's kinda cleared up and I'm not as bloated as I feel a few weeks ago. But I'm still not getting a period?! My question is this how vitex work? I don't even know if it's working for me or not. I also get cramps almost everyday like I'm gonna get a period or something and it's nothing. Which I never get any cramping before a period.