No worries.
I used to use lullaby conceptions OPKs. The directions also noted being consistent with the time you test. I used to test after I got home from work (so just after 5pm). Once you've had a positive there is usually 24-48 time frame in which you'll O.
As mentioned previously (sorry can't see who posted on my phone) if temping and OPK'ing you'll get a better idea of Ovulation and over time (hopefully) see a consistent pattern.