Thank you for your query.
At 5 weeks, the B HCG
value is definitely very low, however it is doubling as it should.
Do not rely on the progesterone
She definitely needs pregnancy
supportive medications, hormones and supplements.
Consult a gynecologist at the earliest.
A serial ultrasound
would be a better tool for monitoring the progress and viability of the pregnancy, instead of confusing and multiple blood work.