My kitten suddenly became lethargic at 1pm and won’t eat or move. It’s been 8 hours and he is still the same. His third eyelids are showing and covering half his eyes but they are white with no sign of infection. He doesn’t vocalize like usual or move to eat. Just very tired and barely moving. I’m going to the vet tomorrow but is there anything I can do? Or any possible reason? He is an outdoor cat so maybe something outside happened.