Letrozole questions

DisneyMom🐶👦🏼🧒🏼👶🏻👼🏻🌹🦄 • Busy mom of 3 under 5 Proud mom of an amazing Preemie Warrior and an Angel 👼🏻 in Heaven. Hoping for our 🌈 baby soon.

I took my first dose of Letrozole Aug 15-19 days 3-7 On Monday I felt sharp off and on pain where my right ovary is. Is it possible to ovulate that early on cycle day 6? That’s the only day I felt it. What day did you ladies ovulate on Letrozole? When should I start testing with OPK’s? New to this med so any information would be appreciated. Also what’s the difference of taking it days 3-7 vs 5-9?