Low hcg?


Anyone have very low hcg and go on to have a healthy pregnancy? I got a positive on a line and digital test very early at 10 dpo so I called to get an appointment with my ob/gyn right away. They said I needed a quantitative hcg test before I could make an appointment. At 11 dpo it came back at a level of 21. They seemed concerned when they called me and said it's "borderline" and I could be having a miscarriage so I'm getting another blood hcg tomorrow (at 17 dpo). My line tests are consistently getting darker and digital tests coming up as positive quicker. Thoughts?