Is my transmission done?

Was driving my 02 Astro van and heard a high-pitched whine when accelerating. When accelerating it did not downshift to gain power. Was able to make it home but when trying to park, reverse no longer worked and it felt like it was in neutral. Could it just be my reverse switch? Please tell me that's what it might be. I def am not putting a new in this thing, it's been nothing but trouble from the beginning. The only plus about this van is the perfect size to work in and can get in most low clearance garages.