I had my first scan when I was only 9 weeks and was prepared for them to have trouble finding the baby as it would be so small but she found it straight away, saw the heart beat (which did take some time to find) and the baby even wiggled it's arms and legs.
They don't look like much at that stage but 11 weeks is good and you should be able to see much more. If at 11 weeks everything seems fine on the scan your chances of miscarrying are very low!!
Good luck and I hope it goes well for you!!
