Possibly going to have a miscarriage, low progesterone😭😭😭

I have endometriosis and just found out I’m about 6 weeks pregnant. They’re suspecting this isn’t a viable pregnancy 🤰🏾 since my progesterone level is only 4. My HCG level is 2400 which to me is fairly low. I go back on Friday to see if my hcg levels double. I had very light spotting that’s gone away and today I’m experiencing abdominal pain. I had unprotected sex twice with my partner before getting pregnant so I thought it was really meant to be. I will be sad if I lose this baby.