Can your hcg still rise if you miscarried?


My dr told me i was miscarrying about a week ago at 6 weeks 3 days and i havent bled havent cramped and ive been to the er since because of nausea and dehydration and they told my my levels had went from 13,265 to 74,337 within a week which i think they said was doubling every 3 days, would this still happen with a miscarriage? Could it be a missed miscarriage? Im so confused im going ti see if another ob will give me an ultrasound to make sure. This has been such a crazy experience its insane.