Cats can get sore throats. Perhaps your cat strained his vocal chords when he screeched at the other cat. Is he eating and drinking normally? Running a temp? You might see if there is a pain reliever that can be administered or a shot of short acting cortisone. Otherwise, hopefully it will heal in due time.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher