Implantation bleeding or miscarrige?

Two days ago I started having this discharge. It’s gotten slightly darker colour now but no heavier. So I’m on my third day now of this spotting I guess I should be around 5 weeks pregnant right now. I’m not sure if it’s implantation or I’m miscarrying soon. I had a missed miscarriage a year ago. I went to the hospital yesterday and the dr didn’t offer much comfort or opinions only told me that my hcg was definitely there (whatever that means) I should have an ultrasound in the next two days but not sure that will be of much help either.