How long do you u continue to get a positive pregnancy test after miscarriage

I've been TTC#2 for 18 cycles. Finally got a bfp on 10/12. I spotted for a week. My doctor said my cervix was closed and it's probably just Implantation bleeding.

Now, my doctor thinks I had a chemical pregnancy because my hcg was low(67) and dropped to (53). And because I was spotting for that week. I know this isn't going to be a viable pregnancy but I don't believe I had a chemical. I barely bleed each day. I do believe I will eventually miscarry.

I'm still getting positive pregnancy tests. How long will this go on? I just want this to be over with already because my heart can't handle waiting any longer.