Help on HCG levels !!

Mila • Pregnant with Baby #2 (IVF) || Baby #1 in Aug 2020 (IVF) || Past: 3 ectopic

I have had two ectopics and finally got my BFP like 6 days back.. I’m a lil anxious on the Blood levels.

On 14 DPO I got a BFP with 30 BHCG

16 DPO was at 77

18 DPO is at 149

I know the count is kind of doubling, but are these too low??