Lh surge a week after period?

Genevie

I bought an OPK a week ago, and have been doing them every day since. Just testing the waters to get used to it. Today, it was positive. Everything I've been reading says ovulation is 2 weeks before your next period? I'm confused. My last period was just short of two weeks late, and I was so excited. But we all know how that goes. Just need some input into this positive opk, I'm new to this.