Low progesterone

Ally
So, I am 4 weeks 4 days and had blood work done twice this week. HCG more than doubled but progesterone is low and stayed low at the second blood test. I was prescribed progesterone to help raise the levels and on Wednesday I am having an ultrasound to rule out an abnormal pregnancy (ectopic pregnancy) and now I am panicked! My nurse said she highly doubts that's the case but...
Any advice? Stories? I know the % of ectopic pregnancies is like 1%- 2% and I don't fit in any category associated with high risk for that but I did use clomid and HCG shot. Don't know if that has anything to do with that! 
I'm hoping my progesterone is just low and the meds will help! But waiting a week to find out will be hard!