Lost Elderly Tuxedo Cat in Harrison, ME

Missing. My Itty bitty black tuxedo cat in the area of Hamlin and Vacationland roads, Harrison, ME. She opened my sliding screen door and snuck out. She is almost 13yrs old, weighs 6 lbs and is skittish. Has only ever been an indoor cat. Just moved to the area last month. We have been searching high and low for her. Her name is Mittens. Usually comes when called and very vocal.