OPKs as HPT

So I have an 8m old daughter that I breastfeed, but not exclusively as she eats solids... I'm on the mini pill but I am relaxed about taking it bc my husband and I don't care if we get pregnant again as we are going to actively try in Jan. I have not received my post partum period yet, and I have now had 2 OPKs show positive. Not super dark positive like when your about to ovulate but enough to see on the stick. So my questions are can they detect a pregnancy? Is my body actually ovulating without a period?