Very nice

Did you keep shooting for a few minutes after? if so you may have caught the Cygnus spacecraft which is basically on the same orbit but a few minutes behind. Would have been 4-5 mag less bright than the ISS but it looks like you would have caught it.
I watched the ISS and Cygnus pass over Sydney last night and I could see the Cygnus even through that light pollution! (though it was a couple of mag brighter than tonight's pass).