Help!

K
Hi! I have a question.... I'm on CD 35.... This is my first month off BCP, so, maybe I have some mess on my body. Well,
​The question is..... Why the "green" days move when I don't have AF. I always listened that day 14 was the "stronger" one. But, my green days still moving because AF don't come! Soooo, my 33% day move all over the month.... This shouldn't be happen, because still being the day 14, even if AF don't show up.... 
​I'm confused.... I dek if any of u can understand my doubt, my language is Spanish so I try my hardest to explain my self haha....
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