Bummed out

So I've been thinking....and I'm a bit upset because I've had no ultrasound yet and I'm seven weeks. I see tons of other women who have ultrasounds done at 5-7 weeks and I feel like if their doc. is doing so, why can't my doc. perform one on me?!? I just want to know if everything is ok. We can't see through our uterus and inspect our babies on the way, so I feel as if I should see someone else to get help. I need reassurance!! What would you mamas do??