3 days +OPK

Hey ladies. First time using opks so I'm hella confused. I got a positive opk (same colour as control) on CD 15, I got a peak (colour much darker than control) on CD 16 and another positive opk on CD 17. My question is when do I ovulate? Have I already? How many more days should I baby dance(so far it's been 3 days in a row)?

I know some people don't test after their first positive but I really want to make sure I don't miss my fertility window.

I would just like some insight.