6 weeks, maybe miscarriage.

This is my first pregnancy and I started spotting yesterday. I was told it could be normal but husband wanted to go in to give me peace of mind. We got no peace of mind. My hcg was very low and they could not see anything on ultrasound, they think it may be too early and I could be off on my timeline. They want me to wait til tomorrow to see if the levels are going up so they can know more. I just wanted to post to have some reassurance, I'm so scared, I'm still only spotting and barely cramping but the waiting is so depressing and anxiety inducing. I have so many "what ifs" going through my head and I'm exhausted from it. Just wanted to see if other expecting mothers had the same feelings in similar situations.