Line progression

Jessie

I got my first + on a CB at 10 DPO. In pictures is 11 DPO. I had bloodwork 12 DPO and my beta was 24. Another draw 14 DPO and it had only risen to 30, my doctor said it doesn’t look great but could still be viable. I figured I was going to have a chemical but the line doesn’t really seem to be getting darker, or if it is it’s very faint. Thoughts? I am now 18 DPO.