Sorry your feeling so stressed out. If i were you i would go get another opinion from a different doctor. My Doctor is adament that without enough progesterone a healthy pregnancy cannot continue (the placenta starts to make the progesterone at around 10/11 weeks i think but until then you need to be rpoducing enough yourself.)
Also as far as i can tell some doctors know alot about this and others are completely clueless. This is my 4th baby and my 7th pregnancy and the first time anyone has mentioned it, I had never used this doctor before.
Also, are you in Australia? From what i can gather they use a different scale to measure in America? So my original levels of 52 would have been about 14 in america (i think you divide by 3.7, someone correct me if i am worng about this) and my doctor said he would be happy for me to be over 90 at around 8 weeks pregnant (that would be 24 in america). Also as far as i know it is better to start the progesterone as soon as possible if you need it, my starting at 8 weeks was somewhat late (my fault as i didn't have the tests done until then) and i think my doctor wasn't holding out much hope.
Hope this info helps even just a little bit, in short definately get another opionion from someone who knows about progestrone in pregnancy!!
Good luck let me know how you get on xxx