So this month I had my second peak positive opk. I'm using he clear blue advance digital monitor been testing for 5 months last month my opk tested peak on cd15&16 this month cd 10&11 is this normal to have such a change? I think I need to keep monitoring for a few months now. I think it's possibly down to my body adjusting to its new smaller size and healthier diet. I've been slimming since 3rd December 2015 and lost 3 stone 9lbs joined the gym and upped my activity a lot!