My fish is a female Betta named Beru; I've had her for about 3 weeks.
Last Sunday (5 days ago), she started floating around at the top of the tank - but would eat food whenever it was dropped into the tank. Today (just a few minutes ago), I noticed that she wasn't swimming straight; she was swimming in circles and twisting around, and hasn't eaten food for a day or so.
I have some plant bulbs (labeled "Betta plants" at PetSmart) in the tank that she has been gnawing on, and now they're sprouting white tendrils and are covered in some slime. I washed the slime off of the plants when I changed the water Monday.
Currently, she's lying upside down at the bottom of the tank and her gills are moving a lot (sort of like she's hyperventilating).
What should I do?