What is this on my ultrasound?

I asked the ultrasound tech but she claims she can’t tell me anything. My doctor just told me come back in 1 week for ultrasound and blood work.

There’s a line in my gestational sac.

A little background I am 7 weeks 5 days measuring 4-5 weeks. Doctors are unable to locate baby. I’m hoping they can rule out ectopic pregnancy but they just say nothing in my tubes or it may be too early. They haven’t mentioned anything to me at all but just “come back in a week for ultrasound and bloodwork” I’m assuming Blighten Ovem

Current blood test results

HCG Levels

12/8 Tuesday 3PM - 2,842

Progesterone 18.9

12/9 Wednesday 9pm-2,455

12/11 Friday 8am-2,608

12/11 Friday 2pm-3,232

12/11 Friday 7pm 3,094

12/15 Monday am 3,435

Progesterone dropped from 18.9 to 11.8

No recommendations for progesterone supplements.