I'm on my second cycle of Clomid and still haven't gotten a positive OPK or temp rise and I'm on CD18 now. Last Clomid cycle I had a positive OPK on CD16 and O'd on CD18. I was told I should O 5-9 days after the last pill which would be today. Is it normal for it to vary this much? I figured hormones should make it pretty stable like a BCP.