HCG levels

Lisa
So, this is my third pregnancy. With #1 the highest my levels got were 874 and #2 was 953. I lost the baby both times. 
I just went to the doctor yesterday and my level was 2,794 but couldn't see anything in the ultrasound. According to this app, I'm 4w5d. They gave me no estimate of how far along or anything. 
My question is, does that level sound appropriate for that far along? I know each pregnancy/person is different but I just need some piece of mind lol.