Hi everyone, I've had my positive opk a lot later in my cycle this month and it's lasting for quite a while. Any reasons for this ? Do I write this cycle off and take it my body has had a malfunction this month ? I missed CD16 and 17 of testing had alot going on so not sure if my surge started on any of these days but definitely a peak on CD18. I usually get a positive CD13/14. See picture below.