Feeling anxious!

Kathryn
Hello all!
My partner and I have been ttc for a year now after a miscarriage.
 Last month my period was 3 and a half weeks late. 
I've had fertility blood tests done and all is normal apart from the fact that last month I didn't produce an egg at all as my progesterone levels are too low. 
What does this mean? 
Is that normal? Is the progesterone level something that changes? 
I'm 34 and getting very worried that I might never have a baby. 
Has this happened to anyone? 😳 x