My OB is denying my request for progesterone supplementation

I am currently 5w pregnant with my rainbow peanut 🤍 And have been monitoring hcg and progesterone frequently. My hcg levels have been rising appropriate - but my progesterone went from 18 to 13 this week, within 48 hours.

After an early loss last cycle, I am super nervous and requested my OB prescribe progesterone supplementation for me. She declined - and said she only does for values of less than 5. And she also will not do any more labs on me until my first ultrasound due to my hcg rising well.

I am scared and frustrated. Am I being unreasonable for wanting to push the supplementation? I am so fearful of losing my rainbow and would feel more at ease with a script