Pregnancy after Miscarriage Question

So I miscarried in September and recently found out that I'm pregnant again, 5 weeks and 3 days today (exciting and terrifying). Anyway, when I went to my OB appointment for confirmation, they wouldn't give me an exact due date and they don't even want to do an ultrasound until I'm 8 weeks along. 8 weeks?! Is this normal? I feel like this time they are walking on thin ice around me instead of congratulating, etc. Anyone else experience this?