OMG, I just googled "5 week ultrasound" to see what others have seen and I came across this disturbing image. LOL Seems it's from the Huggies site.
Now I can't help but think of you like that Lauren. Is that your uterus I see? :P
5 weeks pregnant - Find information about pregnancy at Huggies.com.au
Nothing is totally normal! My searches showed a lot of black dots with nothing inside. Baby is SO tiny. Look at your ticker. 3-5 mm. Have you LOOKED at a ruler? Also...aren't the dr. office u/s machines often not so great?
Babies grow at different rates, and even according to your ticker you babe is just 3-5 mm THAT IS TINY! plus they might not have the latest greatest US machine in office, most offices in our area generally send you out to an offsite to do the in depth US's which make me think they are either not skilled or do not have the best machines.
Stay calm, ask for an appointment in a couple weeks or so, and get another US.
ETA: LOL heather just posted basically the same thing at almost the exact same time, Great minds think alike!