Hcg levels

Carolina

I’m currently 15 weeks and four days pregnant and I’ve been going to get my hCG levels done every week from my understanding they’re supposed to drop around the stage. My nurse practitioner is quite worried as they have been dropping but are still with the norm she has booked me an emergency US tomorrow and now I’m scared and anxious. I’ve had spotting here in there for the last two weeks which has been brown but have had no heavy bleeding. Has anybody else experienced this? 😰😰😰