"I was the last talk of the last day. Only about a dozen people attended that talk."
From the title I thought literally NOBODY showed up. I've done talks at 8am on Saturday in a room built for several hundred people where only about a dozen showed up and it didn't even occur to me to be upset. I was surprised & happy that many people showed up! I guess my expectations are low.
Dozen people or so? So long as at least a few of them are paying attention, I'm fine with that. I've had small audiences where I've ended up chatting with people for 30 minutes afterwards. I'm fine with that.