OPK four days fertile???

Kyrstiana • Married to the love of my life for one year. 22 years old. Currently TTC!
I'm new to all of this ovulation tracking, TTC stuff and as I'm sure you know it's very confusing! 
Anyway, I've been using digital Clear Blue OPK, and for the last for days it's been flashing and saying I have high fertility. That's great! I think. What does this mean? When am I supposed to ovulate? Why is this SO confusing? Why can't a stork bring me a baby??