No sac visible

I’m finally pregnant, or so we think. After our last miscarriage a year ago, I took a pregnancy test and it said positive which made sense since I’m so sensitive and emotional. But we went to our doctors appointment yesterday and in the ultrasound the doctor couldn’t find a sac. My blood hcg level is 895 so I’m really sad to think it could be a miscarriage? Or even a tubal pregnancy. Feels like the options of the outcome being negative than positive are two to one. Has anyone has a similar experience? Maybe too soon? According to my lmp I should be 7wks 4 days but again, that’s not what’s showing in an ultrasound.