Ovulating early?

BKM

I had birth control removed October 30th. Was nexplanon ive been tracking my periods/fertile days. I know all bodies are different but is it possible to ovulate earlier then what an app says? I’ve been testing with clearblue digital and the cheaper LH strip test. Once you get both estrogen and the LH surge the smile face with stay for 48 hours. If I truly ovulated today or yesterday whats the earliest I can test? I went from “not fertile” to peak in 1 day.