Dpo counting question

Marissa β€’ TTC my rainbow πŸŒˆπŸ‘ΌπŸ» Mommy of an Angel born in Heaven 12/9/2020πŸ‘ΌπŸ»

Should I count the peak test day as ovulation day? So say I peaked on the 1/27, would I could 1/28 as 1dpo? This always confuses me