Plebada is a cool slang word used in Mexico, especially in the northern regions where this style of music originates. It's an informal way to say 'the crew', 'the gang', or simply 'the people'.
In the song, the artist sings, "Que ando bien loco dice la plebada" (The crew says I'm going crazy). He's saying that even his friends have noticed how lovesick and desperate he's become. Learning this word gives you a taste of authentic, modern Mexican slang!
This song is a perfect soundtrack for when someone is ignoring your calls and you're starting to lose your mind. Tito Double P is completely stuck on someone who won't pick up the phone. He calls and gets sent straight to voicemail: "Le estoy marcando y me manda al buzón" (I'm calling her and it goes to voicemail). He even sees she was online, but she still didn't answer. Her friend's excuse that she's asleep doesn't fool him for a second, because he knows her pattern: "Siempre es la misma cuando anda tomada" (It's always the same when she's been drinking).
He's feeling terrible, or as he puts it, "ando que me lleva la chingada" (I'm feeling like hell). The chorus is just a sad list of everything he misses about her—her kisses, her body, her voice, her love. He can't understand how she could forget everything they had. The feeling gets worse in the second verse when he points out how awful it is to be alone during "el mes del amor" (the month of love). He's so desperate he says he needs her in his bed just to be able to sleep.