Hi Summertime, I don't know why your counsellor responded like that, but as long as you are working through things, I think its OK.
Sometimes my T ends sessions early and I wonder the same thing, as others seem to take the whole 50 mins, but then again I don't take part in the chit-chat that my T tries to instigate at the end of session. Maybe thats why I always leave unsettled.