Your brain is not really cooperating so you just try the first spell that pops into mind that wont actually cause any pain to the rooster! This better work.
But then, the rooster starts crowing! At the very moment it does, the basilisk seizes, screeches and starts rushing back towards the entrance it came from. It doesn't quite make it there, it reaches Voldemort and falls down, face forward right where he stands. Your heart skips a beat when you think it might have crashed Ginny as an enormous scream echoes through the Chamber. But you soon realise that the scream belonged to Voldemort, who is fading away but not before he locks eyes with you. It's clear that this is not the last time you'll be seeing him but all that is irrelevant at this moment and you run to see to Ginny.
As you kneel down and explain what happened to her, she's so terrified and confused, you notice that an old Tom Riddle's Diary has been pierced by the basilisk's fangs upon it's fall. That must be where Voldemort's memory was coming from and now that it's damaged, it could not contain itself any longer.
The rooster seems to have really taken a liking to you, I suppose you got a new pet, hopefully Hedwig doesn't mind! After some adventures you can't help but bond! You, Hermione and Ron would know!