CD 16 no positive opk yet

Julie • Pregnant with our rainbow baby! 🤰🏻🌈🥰
I'm on cycle day 16 and still haven't gotten a positive opk, not even a faint line. What's the latest you've ovulated in a cycle? This is our first time using cheapy opks. We are TTC 5 months now and used opks another month but ran out before I got a positive. Is it possible I don't ovulate? I'm scared because I'm not even getting faint lines on the opks. 😞