High to peak fertility in a few hours?

Kristy • Son #1 born June 2016 💙👣 Son #2 born February 2019 💙👣🌈

So yesterday morning when I tested with Clear blue digital advanced I got the flashing smiley at 5:45 AM, then I tested again at 12:45 PM and got the solid smiley. I couldn't believe how fast it was, has this happened to anyone else? When I got pregnant with my son I think I had at least a day or two of the flashing smiley first 🤷Got peak fertility again this morning (on clear blue digital, not advanced) so hopefully I'll ovulate today!