5 weeks is too early to see anything. Ask for a repeat ultrasound in two weeks and you should be able to see the baby and a heartbeat. Good luck.
5 weeks is definately too early to see the fetus. i had a scan at 5 weeks 2 days and saw a the sacs then went back at 7 weeks and 2 days and there was the fetus and heartbeat. Good Luck
You should not be worried at all. It is normal to only see the sac and yolk sac at five weeks.