Peak OPK reading 5 days before period?

I’m so confused and getting a little frustrated not knowing when I’m ovulating. In December my period was from 12/15 to the 19th. Then my OPK gave me high fertility readings from 12/29 to 1/6 and gave me a peak reading on 1/7, then started my period on 1/12 to the 16th. My <a href="">glow app</a> and my other app says I’m supposed to be fertile starting yesterday and that I should ovulate the 28&29, but the OPK says low. My cycle is usually 28-30 days so all this is just so confusing. Anyone having similar issues and have any advice? It doesn’t seem normal to ovulate a couple days before your period?