My chameleon usually lay their eggs all at once. But just leave the sand box in there for awhile and see if she will still continue laying. If she covered up the eggs, I would suggest you dig up the eggs (put those eggs in the same orientation when you dig them up, incubate them in moist perlite/vermiculite half buried) and then place the sand bucket in her enclosure again. She might need to warm up a little and regain some strength before digging.
There is one incident where there is a female panther laid 22 eggs and left the 23rd in the body. She died soon afterward.
11 eggs doesn't sound like a very big clutch. Mine have never done anything but lay the whole clutch at once....but I have heard of others saying that theirs didn't. Its not normal IMHO though. I would do what pohchunyee said and take the eggs out to incubate them and then put the container back in in case she has more to lay. If you took her to a vet they could do an x-ray to see if she is retaining eggs. If she is retaining eggs, then they could give her a shot to help her lay them...or tell you if there is a physical reason why she isn't.