8 w 2 d and no baby on the ultrasound

Rachel
So I went to my first ob appointment last Friday, I was 8 weeks and 2 days, and they couldn't find the baby on the ultrasound. The doctor said that she saw the heartbeat but couldn't find the baby, which doesn't make any sense to me. So we did some blood work and they told me today that my hormone levels were normal for an 8 week pregnancy but that's all the information they would give me. 
Has anyone had this happen? I'm just really confused and freaking out a little bit.. is it normal for the baby not to show up on an ultrasound at 8 weeks?