Pregnancy after miscarriage story

On October 31st 5w4d I began bleeding. (I had been cramping and horrible back pain the entire time) Went to the hospital and my HCG was 125, continued to bleed and followed up with my ob and my levels 2 days later were 267. I continued to bleed for 3 more days. Followed up with my doctor the following week and my levels were at 6 followed by 0 two days later. 
Well I was waiting for my period to come to get on birth control but I had a hunch my eggo was preggo again. Sure enough I was right! I had my first positive test on November 30th. I decided to wait until the 10th to get bloodwork incase I lost the baby again and my levels were 3,895 Tuesday the 15th they were 19,231! I have been feeling so sick for the past two weeks, food aversions to everything but pizza, ice cream and cereal!
 I go for my ultrasound on Wednesday and I'm nervous. I have no idea how far along I am. I'm afraid I'll have an empty sac or its a molar pregnancy since I got pregnant after my miscarriage so quickly. 
Has anyone gotten pregnant after a miscarriage without a period in-between?