Ovulation Tests

Laura
I have been using Clearblue Digital Ovulation kit and for the past 4 days have shown high fertility (the blinking smiley face), but not peak fertility. I miscarried in June at 7 weeks, so this is my first regular cycle since and I am curious if it isn't because of that.  
Has anyone else experienced this? If so, how long did the blinking smiley face last for you?