Help me out!

These lines seem pretty dark to me to be considered low same strips on the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> keep changing from positive to negative when I scan them. Any ideas? This is my first time using OPKS and I’m a little overwhelmed. Glow had me at ovulating 2-3 days ago but there was nothing really on the test line now it has updated to tomorrow for ovulation after the OPKs were entered...🤷‍♀️