HCG Levels

Ok so I found out I was pregnant yesterday 2/22 and went for a blood test to confirm. I got the results back and the level was like 41086. The doctor is thinking maybe 5-7 weeks possibly but wants me to do another blood test tomorrow 2/24 to see if levels keep rising. She is concerned because I was spotting a bit on and off before I had found out. I really have no symptoms yet minus a bout of nausea here and there. What do you all think? My first ultrasound is Monday 2/26.