How did vitex affect you? Did it help you in any way?

Ive been taking vitex for 5 weeks now. I'm on CD 20 and still no positive ovulation test. I have had some random pink spotting some days which I guess is from the vitex balancing out hormones. But could vitex prevent me from ovulating? How did vitex affect you when you took it? What were your periods like on vitex?