Understanding opks


I’m just coming off of the nuvaring. I took it out last week to have my period and didn’t put it back in. My husband and I decided that we are ready to try for another little one. I had my period (which was super super short and light but tested and got a bfn on my pg test.)

I started testing with opk yesterday and got the “low fertility” l. Test tested again this morning and got the “high fertility” I’m not sure if it is from the leftover hormones from my birth control or if im actually getting ready to ovulate.

Anyone have any knowledge about this for me?