I was worried about that, at the time, Nora. I thought maybe you jumped to conclusions about why he wanted to talk to you. But that's not the kind of thing that happens out of nowhere; you've obviously been unhappy there and with him for a while. Do you need to work there? What are your options? If you need to work there, for whatever reason, I wonder if you can't pro-actively schedule a "clean slate" meeting with your boss (and maybe HR if you think that would be a good idea). One where you get it out there that you'd like to move forward into the next year with a positive attitude, and ask what you and your boss can do to make your environment more pleasant. Hell, this might not be do-able, but I'm trying to think of it from the perspective of a frustrated boss, too.
I think it was not okay for him to ask you to run a personal errand for him, with or without rain. So he might be unsaveable in that regard. However, if you need to continue to work there, it might be in your best interest to suck it up and ask for a "clean slate" meeting.