progesterone 0.4 CD 21

Mary • 29. Momma to 9 & 10 year old girls, and a one year old boy.
Just a bit of back information.. 
cycle has always been around 32 days (for 5 years or so)
TTC close to 1 year, MC in Sept. 
Cycle is now ~40 days, which sucks because every month we go through the "am I late?" "Is this it?" "Have we finally done it?"
Talked to doctor, I've had excessive weight gain, often lethargic, and my fuse has been shorter than normal 💣. 
My thyroid results came back normal, but progesterone was 0.4... with my cycle being approximately 40 days each month, does this mean I didn't ovulate? Was it an incorrect time for the level check with the longer cycle? 
Nurse said it's lower than normal, but it wasn't until after hanging up that I wondered if it's lower than normal for a "normal" cycle length?