Anyone having issues with low progesterone?

according to my LMC im suppose to be 7 weeks 4 days. I had a positive pregnancy test with what i believe was implantation bleeding the day of my expected period last month. I had my hcg tested along with progesterone, hcg was 414 and progesterone was 14.5...i had an appointment with my obgyn today, no heartbeat was heard and she said i may be too early on.i also did mention to her ive been spotting and light cramping for 5 days now so they checked my hcg and progesterone, my hcg was 12,531 but my progesterone was 4.7! Ive been researching and every where i look it says thats a very low progesterone level. Im worried this pregnancy will end up in a miscarriage. Has anyone had any similar experiences?