Positive test with only 2 HCG?

Bria • 30 years old - Married - 20 month old

I had an MC 31 days ago and was cleared to start trying right away. Bloodwork was done Monday and it was 3. Yesterday it was 2. But I’m still seeing a faint positive! I’m so confused. Has anyone had positives on FRER with super low HCG. Sensitivity is supposed to be 6.5