Good number???/update

I ovulated on Sept 22nd and got my first hcg level back today and it was 27.5 I'm not sure what it should be this early. My period wasn't due till yesterday. Idk any thoughts??

Update:

Mon- 27.6

Wed-36.3

Fri-55.6

It will only be 3 weeks Sunday. I know it isn't doubling yet but I'm getting closer. Is this ok for being so early??