tracking with OPK afternoon

Amanda • 27, Married, 1 Boy 1/17/18
I have read a lot of women say to test in the morning and afternoon with OPK( using clear blue advanced digital) Should I bring them to work with me? What Cycle Day should I start testing twice a day? I have been testing since Cycle Day 6 just to be safe and have had all low fertility. I am on Cycle Day 9 still low fertility. Last month I didn't get any high and just went straight to peak 😭  Should I start twice a day tomorrow? any feedback would be helpful!!!!  Our plan is to BD every other day till peak result that BD that dat and day after. Then skip a day and BD one or two more times to be safe....