Opk question

Kay

So last night around 9:30pm I used a clear blue digital and got a negative reading (empty circle), this morning at 8:45am I got a solid smiley. We BD’d right away by 9am lol. Weird thing is I never even got the flashing smiley it just went straight to solid, has that happened to you before 🤔? Today is CD12 for me btw