My gestational sac at 5 weeks 6days. only 2mm, hcg leve from 4weeks 6days 252 increase to 765 after 4 days. is it normal?

These values are: below average if the gestational age has been calculated correctly. At 5-6 weeks from conception, the gestational sac measures from 4 1/2 to 6 1/2 mm and the HCG level is anywhere between 10,000 and 100,000. I assume you will continue to be followed closely over the ensuing weeks and I hope you will get some reassuring news. Dr. Anne.