First Ultrasound at 13 Weeks?????

So I had blood work done at 5 weeks 2 days... and results came back good. My levels were where they should be. I saw my doctor today for my first prenatal appointment and she booked my ultrasound for Dec.13... I will be 13 weeks at that point?!?!?! So i asked her if I should have more blood work done so we can compare the levels? (Make sure baby is still growing).. she said there is no need ... if ur pregnant your pregnant.. Im a first time mom and am worried shitless that something bad will happen. I want confirmation everything is okay!?!. Anyone else have a late first ultrasound date? :( Is this normal?