Short cycle length

I’ve been using the Clearblue Fertility Monitor with the purple capped test strips for half a year. I have charted for over a decade and added this for more information since my cycle has been very gradually shortening (ave. 32 days 3ish years ago down to 27-28 this past year). (We are not trying to conceive.)  I’m 43 and close to the age when my mom started to have fluctuations before she entered menopause around 45. This cycle I got to the ninth day of the monitor asking for tests. All but the first were High fertility. Then yesterday (cycle day 17, 9th testing day), I got what I’m assuming is my period. The flow is typical and still happening today, plus I’ve had some minor, normal like cramping. My test strip this morning gave me an error but I didn’t catch if there was an error code. It wanted me to rest again, but honestly, I think I just needed to set up a new cycle instead, which is what I did. What would be the recommended action in this situation? It might be too late for me to fix it now, but at least I’ll know for future reference. Thank you!