Breastfeeding, 3days late period and positive opk test

Erica

So I am breastfeeding for 6 mo. My period is 3 days late and I’m very regular. Last month was the first time I got my period back. However I took an opk test thinking it was a pregnancy test. Holy crap way to scare the crap out of me. But it’s positive. The lines are the same color. I was convinced I have already ovulated. This happen to anyone? I have cramps, sore nipples when pumping and breastfeeding. I was convinced my period was coming instead.