Why day 21 progesterone testing failed me

got told to test my progesterone on day 21 to confirm ovulation. my cycles were 32-40 days, sometimes skipped entirely. tested on day 21, came back detectable, GP said looks fine, probably just irregular cycles. took 6 months and pushing for an endocrinologist to retest: we need an LH surge first, THEN test progesterone 7 days after.

no LH surge found. i wasn’t ovulating at all. the standard testing protocol failed me bc my cycles don’t follow the textbook 28-day model. anovulation diagnosis almost got missed because of how testing is timed.

how many others got misdiagnosed or nearly missed bc standard testing assumes regular cycles? asking because i’m trying to figure out if the protocol itself is broken or if it’s just not designed for PCOS