I had an hcg done at ~3.5 weeks (11 days after conception) and it was 7100.... is that way too high to even be multiples? i'm worried it's molar.

High for 3.5 weeks: 7100 is high for 3.5 weeks. A common cause of an elevated HCG is an incorrect date for conception. Unless you know the date of conception with certainty (because you had in-vitro fertilization or other advanced reproductive technique) this is a likely cause. Other causes are multiples or a molar pregnancy. The only way to know is to let time pass and get an early ultrasound. Best wishes!

HCG values: HCG values are coordinated with the number of weeks gestation and come with approximate normal value ranges for every lab company. You need to ask your OB MD about whether these values are normal in the context of your physical and ultrasound examinations.