First time using opk’s, doesn’t match app

This is my first month trying as well as my first month dealing with opk’s so I need you guys help and advice please. My period ended Monday, I started checking with CB digital opk Thursday, (open circle), Friday (Blinking smiley face) and Today (Solid smiley face). Because I entered the information into the app now Glow has moved my ovulation day from Thursday 13th to tomorrow 9th, that mean would mean Glow was 5 whole days off ? I know this is a prediction app but still that’s a lot of days off, I would have totally missed my ovulation day and the leading days, but now I’m wondering about this opk test, Is that even possible to ovulate so soon after my period has ended ? And It literally went open face, blinking to solid, I never had anything two days in a row like other people who used the opk stated. I’m sorry this post is so long but any advice is welcome. Should I listen to the opk and start BD’n ? Do you think the test may be faulty?