Hcg rising slowly?

Got my blood taken Monday night at ER and it was 288 got my blood taken yesterDAY and it was 462. So not doubling. Both ultrasounds showed nothing... I spot all day long. Last week I had heavy blood for about 6 days. I am scared maybe ectopic? Anyone had something similar happen to them? Scared to death it is ectopic 😭😭😭😭