Low progesterone....

Kim • Happy fur baby mom
My OB/GYN ran blood work per my request and he said everything except my progesterone looked good, it was low. I had the blood work on cycle day 12 which would of been 1 day past ovulation or possibly day of. Any suggestions? He had none well except to get an HSG done which will cost me $300. We've only been TTC for 4 mths now but I am 42....