Progesterone levels

Hi everyone, I have been on clomid since the end of November, the first cycle I found out in December I was pregnant but unfortunately had a miscarriage in January at 6/7 weeks. I am now on a higher dose of 100mg clomid. My cycles are usually around 32/33 days so I have a feeling testing my progesterone levels on day 21 isn’t giving an accurate reading and that won’t be when they are at their highest. Has anybody else got longer cycles than 28 days and have their levels tested slightly later? Sending everybody lots of baby dust ✨