Temp not rising with Progesterone?

Kali

Can anyone share some insight on my chart? I got a peak OPK on Thursday the 28th. My temp rose to 98.7 on Saturday, which is my normal initial rise after ovulation, so I assumed ovulation happened on Friday as expected. I started Progesterone on Saturday per doctor's orders but now my temps have declined to 98.5. Any idea what's going on? I thought Progesterone made temps rise.