Ovulation question

MomOf2 • Married 💏 DD:4yrs old 👑 Angel Baby 5/6/2014 👼 My Rainbow Baby! 5/21/2015 👶🍼💙
Okay, so in the past I've had a positive opk for about 2/3 days in a row, what exactly should I make of that? 
​The reason I ask is because I will be triggering this next month with hcg, and I am unsure on when to take my shot. Should I trigger the day of 1st positive opk or wait till the next positive?