Ok so im on letrozole 2.5 mg... im a nurse and work 12 hour shifts (with drive time it’s like 15 hours) so on cd 15 I couldn’t test as normal. On cd 16 I started getting ovulation cramps and thought okay maybe I missed my peak .. I have my cd 21 progesterone test tomorrow but I’ve continued taking opks in case maybe I get a positive and today they started getting dark. Could I be ovulating this late ? I’ve had about 30-31 day cycles the last 3 cycles on clomid and this is my first month on letrozole.