PUZZLED!

Have you ever felt sad for nothing? As you are sitting inside of a dark box in a bright room with hundreds of people? As you feel lonely even though your friends are joking around and talking to you? But that's the thing. You cannot get up from that sadness and you do not know the reason behind the sadness. Is it because you get offended easily or you are just sad thinking of your life? I don't know because i'm in a such situation. I feel sad and down but i want to get outside from this dark box but what i do is just listening to songs to sink even deeper into sadness.