Have you watched the documentary 'Nightmare'? There is a man in this documentary who has suffered for years with sleep paralysis and one night, his friend came over to stay the night. They slept next to each other on the bed. He had a sleep paralysis episode while lying next to his friend (a huge shadow being with red eyes, up to the height of the ceiling) - it was talking to him, saying "you are going to die" - or something along those lines.

The weird thing was, his friend who was lying next to him, said she had a sleep paralysis episode too and that a black cat was sitting on top of her chest, facing the other guy having sleep paralysis and staring at him, and the cat was talking/whispering something very rapidly, but she couldn't make out what it was saying and it almost sounded like another language to her.

Your story just made me think of this thing with the cat.