Day 3 fresh transfer-HCG levels for successful pregnancies?

Hi, I'm 41F and did my first d3 fresh transfer after 3 "failed" IVF cycles. I have a normal AMH and decent oocyte numbers (24, 18, 21 retrieved across 3 cycles), but had trouble making blasts. The few that did reach blast all tested aneuploid, so my doctor recommended a day 3 fresh transfer.

I'm 11dp3dt and had my first beta check-it came back 46.5. I'm pretty worried it's on the low side. Anyone else have success stories with a first beta that low?