hello, i think at 11 months he will understand some things, very intelligent are babies!
i think you have the right idea with sleeping by his cot to keep him settled, as uncomfortable as it is!! that way he is in his room in his bed rather then yours, its just the comfort from mummy he wants - bless!!
i doubt there is any quick solution, we have all done this!!! plus i know people say to just leave him to cry and he will get over it! but thats just so cruel, i couldnt bear the thought of my baby crying in a cot and no one coming!! its horrible!!!
i would just stick to that for now, make yourself a bed by his and then hopefully ( fingers crossed) he will stop waking up and crying for you, then you can slip back into your own bed, plus while he is ill i would stay by him, i used to watch my daughter all night when she was ill!! especially with \ cough, buts that me, a bloody worrier!!!!!
good luck, xx