Can you carry to term with VERY low progesterone?

Hi all! I found out today I am 3 weeks pregnant. My HCG levels are perfect, but my progesterone is EXTREMELY low. I should be devesated, right? Right now I'm just happy that Hubby and I were able to concieve with out medical intervention. 5 years of trying and this is the first time we have been able to concieve on our own. Its a step in the right direction, and my new doctor thinks he may know how to help us retain a pregnancy in the future. I am taking progesterone supplements, even though the likelyhood of this pregnancy carrying to term is negligible. As long as there is a chance, I'll do everything I can. When all is said and done, I dont want to have any questions of "what if". What do you all think?

There is always the threat of ectopic as well. Does anyone have any insight on what i should keep an eye ouy for when it comes to an ectopic pregnancy? I have done a TON of research, but if anyone has personal insight, that would be helpful. Thank you!