Miscarriage??

I believe to be 8 weeks. That’s when the pregnancy test would make sense to be positive too. My doctor is saying I’m 6 weeks 3 days. They said it doesn’t seem like an 8 week pregnancy that stopped two weeks ago, but I’m freaking out. They said to come back in a week to be ultrasounded again. I have been have a pulling feeling and tingling in my lower abdomen, like all my other pregnancies. Which I took to indicate that my uterus and baby are growing. Why would I still have that if the pregnancy stopped two weeks ago? The doctor thinks I just messed up on my dates, but I really don’t think so. Praying for a miracle and that everything is ok. I still feel pregnant. No bleeding, cramping, etc. Thoughts??