When he said "You'll be okay with a "fake cheerfulness" it show doubt and worry about Johnny getting out of the hospital. He knew Dally and the rest of the gang would be devastated but he needed to keep him going and hoping he would recover.
The correct answer is gloomy mood. You can see that Romeo is running away from light, drawing his curtains in order to hide it away completely. He dislikes light and day in general because it means that he cannot see Juliet during the day - they used to meet only during the nightfall, which is why he despises light.
