Ovulation symptoms but no smiley so far.

Rich

I am on my CD16. Hv been opk testing (clear blue digital) since cd 11 and started testing twice since cd13. But hvnt seen any smiley so far. I hv ewcm and ovulation pain one side since yday morning. The blue lines doesn’t seem to change much either over the days.. Can clear blue opk results be flawed?