Lord of Madness

I just got back from a six month business trip, and my 2005 Camry has been in a garage for the duration of my trip. It's been started once every two weeks or so, just to keep the battery from dying. I got an oil change right before I left for my trip, and now that I am back I am wondering if it needs an another one? I've driven it around town just running some errands, and it drives fine. I just want to make sure that I am not damaging the engine.