Furious with my doctor

Karli
Several days and several dozen hours of crying after an upsetting 1st ultrasound, I'm now just left with a lot of unanswered questions!
Tuesday I went in for what should have been a 7 week ultrasound, however what the doctor saw was 5 1/2 - 6 weeks. She said she saw a "healthy gestational sac, yolk sac and fetal pole", she also saw a VERY faint but unmeasurable heartbeat. I am supposed to return in 1 week to see if there's been growth, to see if the pregnancy is viable or not
Now I'm questioning- if she saw a gestational sac, yolk sac and fetal pole is that NORMAL for 5.5- 6 weeks pregnant?? After looking at my last cycle, I ovulated late, on day 20 so is it possible that I am only 6 weeks rather than 7??
I left feeling like I did something wrong, that the baby should be 7 weeks but the doctor only saw 5-6 and that is a problem. I am utterly devastated, but just want to know if I just ovulated late and the baby is right on track for where it should be at 6 😔