Not really civil, no -- considering that those kinds of posts are considered appropriate, and that I've been around a couple of years longer than your account shows you've been, and so would more more likely know what's generally OK here and what's not. "You aren't funny" is just rude -- see PG's extortions about not saying something here that you wouldn't say in person.
I'm going to let your "I've been here longer than you, nyah" comment stand on its own (lack of) merit.
I am perfectly happy to meet you, the next time I am in your town, and tell you that your comment was not funny to your face.