First of all, I'm sorry you miscarried. Even at 11 weeks, women have "plans" for that baby, and look forward to meeting it at birth.
The timetable of human pre-birth development (from the textbook, The Developing Human (Clinically Oriented Embryology) by Keith L. Moore) reveals that at the end of 7 weeks, the embryo becomes a fetus with the beginnings of all essential structures present (head, eyes, ears, arms & legs are all visible).
A 9 week fetus is 5 centimeters long from the crown of his head to his rump (Crown Rump length). A 10 week fetus' CR length is 6.1 cm. And at 12 weeks, it is 8.7 cm. So, you should've seen your little one, about 2.5 - 3 inches in length. It is quite likely that you actually had a blighted ovum (basically an empty egg, that does not develop as described above into a fetus). Or, it is possible that you actually miscarried at a much earlier date, but did not expell the embryonic sac for awhile.
In any case, it still is a loss for you, and, I'm sorry for your loss. I do know how you feel, having lost a little boy at 14+ weeks.
HUGS!
S.