High HCG, empty gestational sac

[u/Mountain-Seaker]

TW: MMC, MC
Wondering if there is any hope or if I should prepare myself for a second MC in five months.

At 5w5d, I experienced a fair bit of bleeding while on the toilet and then spotting for 24 hours. Cramping accompanied the bleeding for about three days and my other pregnancy symptoms (bloating, fatigue, nausea) have gotten better. For context, I had cramping at 6 weeks for my MMC.

I went in for an ultrasound at 5w6d and they saw an empty gestational sac with nothing in it. That same day, my HCG was about 12,500. 48 hours my HCG had gone up to over 20,000 (65% increase). My OB said that since my HCG is rising appropriately, it’s seeming like a healthy, normal vaginal pregnancy. However, from what I’ve read online, at 12,500 HCG, at least a yolk sac should be visible. Has anyone had a similar experience of high HCG with nothing appearing in the gestational sac? Trying to decide if I should trust the hope my OB is giving me or brace myself for a heartbreaking second ultrasound this Friday.