Anyone get weird OPK results ever?

Katherine • Fat, Over 40 & TTC ♥️ Newlyweds TTC Our 1st

So, it's ovulation week and the first two OPKs I take are normal and building. Then today it goes way down. Way. Down. I even took a second test to confirm it.

Has this happened to anyone before? Did I miss it or is it likely to come back up?