Very high Beta/HGC?

Heather
So I was very excited to hear that I was pregnant after my second <a href="https://glowing.com/glow-fertility-program">IUI</a>!  I had bloodwork and ultrasound this morning at 5 weeks and 3 days.  They saw a gestational sac but no clear yolk sac.  "No worries it's early," I was told.  But then they called me with my bloodwork- beta is 20,715 (progesterone is good).  They said that's very high and asked if I was in pain or nauseous.  At that level they expected to see a second or yolk sac at least?!  Something is either wrong or they missed one (and it may not be in the uterus).  Has this happened to anyone?  I go back Wednesday but now I'm a worried wreck.  Joy  and excitement is instantly turning into saw dust in my mouth.