Beta HCG

Hello, knowledgeable ladies !!

Maybe some of you girlies can keep me from losing my mind. Friday 5/13 was 9 days past frozen embryo transfer I went for my infusion treatment and doc decided to do an early beta which numbers came out At 37 and today 5/17 the HCG numbers came out at 106 they saying is low they will do another beta on Thursday they said they want it at least 70% higher 😳 I have had 4 loses and this is second transfer first one didn’t give. I hear so many things about as long as it doubles is what matters. Anyone had same thing happen ? N went ahead with having babies ?