Bleeding while pregnant

So May 5th my “period” started. I was bleeding for 8 days when my period has only ever been 5 at the most. I google causes for a long period and one of the reasons was pregnancy so I decided to take a test. Positive. My OB/GYN office tells me to go to the emergency room. Blood test shows elevated HCG levels but they can’t see anything on a sonogram yet. Today is day 10 of bleeding. It’s not heavy, no clots, no cramps except mild twinges every now and then. I go back tomorrow to redo bloodwork and I’m just kinda anxious. Anyone ever experience this?

Also, I’m only 4 months postpartum. I’ve had a period since about 6 weeks and they’ve all been 5 days or less.