Hcg levels rising but slowly - help!

Hi all,

My hcg levels have been rising but the doctor told me today they think I’m having a slow miscarriage. I started spotting on Feb 1st and have been spotting on and off since. It’s always brown. My last period was December 29th. I had an ultrasound on Feb 12th and there was nothing there. I’ve had increasingly stronger pregnancy tests and my symptoms have also increased. These are my levels -

February 13th : 127

February 18th: 220

February 20th: 330

February 27th : 750

Due to go to get more blood work done on March 2nd and an ultrasound. Do you think there is any hope? Has anyone experienced something similar and had a healthy pregnancy?

Very confused!

Thanks