normal hcg levels...

So I got my BFP 1 day before af was due.  I went to the dr on 11/3 - the day af was due so at exactly 4 weeks.  My hcg was 423.  I didn't get to talk to my dr yet... it was just a technician who called to have me come in to repeat test today (which I did).  I'm nervous... is that a low number?   It's higher than it was w my miscarriage but hard to tell myself to calm down bc what u read online is such a wide range for normal.  Thanks ladies!