She may be an indicator of a change of cycles. One of the functions of Bat (she has powerful medicine in nearly all cultures!) is the marking of the day and night. She rests during the day, whooshes out of her nest at dusk, hunts all night, and hurries home to rest for another day. She keeps her clock as regular as the sun.
She might be marking the change in cycle for you. A red and black bat might speak of earth and night. The red of earth, and the black of the physical realm. So if this is a change in cycle, it is likely to be an internal exploration of your physical self. I like to think of the body as guru – when it acts up it is trying to teach me something, and I think red and black bat might be reminding you of that, too. The black might also mean that much of this physical journey will be internal, in “darkness.”
Additionally, she hangs upside down – getting a unique perspective on your life. She lives in community, and is a superb listener. Australian flying foxes do not use echolocation, but instead have excellent eyesight, which is unusual for bats. Bat is a knower of secrets, she can hear things that nobody thinks are visible.