Irregular ovulation. Need advice!

So I got off Bc pill in june, i’ve been taking opk for the past 2months and my opk’s are all over the place. Like last month I got opk peek on CD7 this month still waiting looks like will be tomorrow peek day but I will be on CD20 tomorrow already. Has anyone had this problem and how to deal with it without ovulation medicine? And yes my cycle is usually between 30-35 days