Help! EArly ultrasound twins!

Backstory- by my last period I’m 5 weeks 0 days, by when I think I ovulated I’m 5 weeks 3 days. On 1/17 I got a positive and a HCG of 53. On 1/19 my HCG was 158. One week ago I had a sudden onset of bad cramps followed by a gush of fluid and blood. I only bled for a short time (a couple hours and lightly). A little brown spotting for 2 days after. I assumed I had a miscarriage and my doctor agreed. 4 days later I still felt off so I took a pregnancy test- super positive. Went for blood work, HCG was 6,600!!! So I just had an ultrasound and there are two sacs! She can’t see anything in either but said that’s pretty normal for 5 weeks? But if I’m 5 weeks 3 days shouldn’t there be something in the sacs?? Did antone have an ultrasound at this time and go back to see babies a couple weeks later??