I have been using the OPKs for two months now and never had a positive (taken around 4pm each day and not drinking anything for at least two hours prior). The darkest I have seen is pictured below. I was on birth control for 15 years and stopped 5 months ago. At what point do I visit the doctor to say I am not sure I am ovulating? Would a clear blue test be better? Any suggestions would be appreciated!