Opk with faint lines

Danielle
I've been testing for the last 10 days. Today(day 10) I didn't get any lines on any of my tests, but before than I got them ( see picture). During the last 9 days I had either sticky or lotion like cm but this morning (day 10) i finally got ewcm. Is it possible that I could still catch an LH surge in opk or should I just stop testing and hope for the best??