I had a vaginal ultrasound today, thinking I was 7 weeks, 4days; according to the ultrasound, I am 6w,2d, with a gestational and yolk sac, but no fetus being found. Is this normal?
At 6 weeks, yes it is normal. And your dates can be off considering implantation can take 1-2 weeks. Sounds like your little one may have implanted late, thus the later due date.
Get a followup sono in about two weeks! You should see a little jelly bean and a heartbeat by then.