Taking Progesterone? should I?

Hi everyone! Last night I went to the ER because I've been having orangish brown spotting for the last few days. I was so worried because I had a miscarriage and D&c; back in October. I needed a peace of mind. They did blood work and and ultrasound and said everything looked good. This morning I had a follow up with another doctor w/i the same practice (my ob out town). I talked to her about how I had my progesterone levels tested the first time but my current ob said she won't test my progesterone unless I start bleeding. So the doctor I saw today said she will prescribe me progesterone and if it helps... It helps. What do yall think? According to Glow, I'm 6.2 weeks but my ultrasound stated the baby measuring 6.4 weeks if that helps.