So I'm currently on cycle day 19, so far my chart hasn't indicated an O date. I'm on a rotation for work so two days each week I wake up around 8am instead of 5am. I think that's what's got my chart confused. I'm going to start setting the alarm to take my temp on my days off too so it can be accurate. But also, I got a positive opk on cycle day 13. I don't know whether to go by my chart and assume I didn't ovulate or go by my opk. Has anyone else experienced this?