Low progesterone at 5 weeks

I had my hCG and progesterone checked yesterday following some cramping over the past week accompanied by occasional brown/pink and one brief instance of bright red discharge. I also had strong symptoms hit prior to the 4 week mark, with low back pain, headache, and breast tenderness, all of which resolved after only a couple of days early on.

At 5w2d / 25 DPO:

hCG 2,263

progesterone 9.3 ng/ml

I made a lab appointment to follow up with a recheck on Monday at 5w6d. The hCG seems like maybe low end of normal range, but I'm concerned about the progesterone. The sample was taken in the afternoon, and my follow up will be in the morning - does time of day have an effect?

I'm currently 36 and this is my second pregnancy (my first just had her 2nd birthday). I don't have any numbers from my first pregnancy to compare.

I'm just really worried about that 9.3 because I couldn't find any posts on here with similar numbers that did not end in miscarriage. Depending on my results next week I guess I'll ask about getting an ultrasound (they're really difficult to schedule) and whether or not to consider supplemental progesterone. If it's just a bad egg I don't want to delay the inevitable.