Opk's

Ashley
Hi ladies, when do you start testing with opk's? I started on CD 10, but don't expect to get a positive till CD 19-20. I use wondfo opk's and even tho I know I won't be ovulating yet the very light test line is super discouraging. Do the lines just turn super dark over night or do they gradually turn darker over time? I took clomid this cycle, on days 5-9 and am really hoping for my rainbow baby!! Trying to look for positive thoughts and lower my anxiety levels! 
Thanks everyone!!