Empty gestational sac at 6 weeks

Louise
Hi 
I was at the doctors yesterday for our first scan at 6 weeks, all the doctor saw was an empty gestational sac. He said he is 90% sure I will miscarry.
My HCG levels have been going up but not doubling, they were 2500from a test on Tuesday morning, the took them again Wednesday evening they were 3700.
I'm so confused they want me back in for tests on Friday after telling me on Tuesday they would schedule me for a d&c after Wednesday's results
Has anyone been in this situation? What was the outcome, good / bad?  I also have a tilted uterus that I've read can cause misdiagnosis
I know I'm probably grasping at straws just want to know if there is any hope.. This waiting in limbo is so hard.. I had a miscarriage in March and was really hoping for my rainbow baby 😞😞😢😢😢