I have PCOS| First cycle using Vitex

YS
I have PCOS and have only tried metformin before realizing that I wanted to take the natural route with less side effects. I am currently taking Vitex 3 times a day,  1,200mg per day. Although I have PCOS, I do have regular cycles of 22 days. I am currently on CD 25 with a BFN. When should I test again?