Yep, I'm a poas addict ;-) and I test in the morning before work and again after work. Sometimes I test again before I go to bed (yes call me crazy) between CD 9 and 17-19. (I have lot of internet cheapies, they work perfectly fine with me and I don't go bankrupt...lol)
Usually I ovulate between CD 15 and 17.
Like slg said, if ur opk is positive, your ovulation is the day after. So u still have the chance to catch the egg.