Please read if you use clearblue advanced digital OPKs

This morning I accidentally used the reader from my last cycle to test ovulation and I got a low reading. Is it possible that I got a low reading because this is the first time I’ve used that reader this cycle and it acted like it was my first test? Or are they really that accurate and that I am low?

Today I am on CD 21 and had 8 days of high (flashing 😊) and then got low this morning. I just want to make sure I am actually low or if I may have gotten it all mixed up because of the readers.

I know it’s possible that I didn’t end up ovulating this month or that I just didn’t have high enough levels to be picked up by the test (according to the instructions in the box)

I’m 6-10 days out from AF (probably closer to 6), and I am feeling some symptoms - light cramping, light nausea, and sore boobs.

Has anyone experienced this? Thoughts? Should I use my 2nd morning pee to test again with the newer reader?