OB Appt #1 not so great

Shandra • Married mother of 2 boys--15 yo and 4 yo; Fourth Grade ELA/SS 👩🏻‍🏫
Went for my first OB appointment.  First day of last period was November 20th, which puts me at 7 weeks.  Went for a transvag ultrasound... and all he saw was the sac--an empty sac.  Took labs to run hormone test today.  Also will request labs from primary doctor taken this past Thursday from confirming the pregnancy.  
Doctors plan is to take labs again this coming Thursday to see if numbers double.  If there is no show of improvement, then we will schedule a D&C.  
I forgot to bring my book that keeps track of my ovulation dates and tests.  But I did tell him ovulated late.  
Any advice would be helpful... thanks. 
*********************UPDATE***********************
So, I went to get bloodwork on Thursday, as ordered by the doctor.  My levels on Tuesday 01/10 were 28407; levels on Thursday 01/12 were 44097.  So it's a good sign that my levels are climbing.  I never got a phone call back from my doctor on Friday--I'm getting this information from my medical portal.  I'm kinda upset that no one called me but I'm trying to pull hope from the labs looking like my levels are progressing. At this point, I have to wait for the doctor to call me and find out what he wants to do.  
Please keep me in your thoughts and prayers to pull through this.  This is the worst thing I've ever gone through.  I appreciate your kind words and support.