I've been using the Clearblue Advanced OPK's, 2 months in a row I got my solid smiley (never had flashing) on CD 13. I know that I did actually ovulate then. Last month I took the tests a few times shortly before my period just because and it was all low. But today, CD 22, I took one and it was peak - solid smiley face. And that was with very diluted urine. I have very regular cycles, 26-28 days. Is it possible I didn't actually ovulate this month or could it be detecting HCG? Too nervous to take a HPT! Help!