Low Numbers šŸ˜«

Hi Girls! I am 13dpiui and the Doctor called and said I am pregnant - but my HCG is 17 & Progesterone is 7.9. I am nervous because I had a chemical pregnancy last year. She said not to worry as long as numbers double on Fridays b/w. I'm taking progesterone injections. Anyone else have low #'s like that?!