Ovulation kit question

Penelope • Married 💚💗
Hi everyone!
I use the Clearblue Easy digital ovulation kit and I got a smiley face one day and then it was not there the next day. During ovulation, how may days should there be a smiley face? Is the LH surge just normally one day? Has anyone else who used this kit had this happen? Is that normal? It was my first month using it :) thanks'