Help me

Sarah • 💑 💍 to my best friend, We have a beautiful 3 yr old boy 3/21/16 👦 and, a baby girl 👧 born 1/29/19 and just found out I’m pregnant with #3 due September 2020 This will be our last one 👶 🍼

I know I missed a few days but when did I ovulate? Jan 1? Jan 2? Also I was at my peak LH on Dec 30 & 31st. Thanks!