My 8 week old son has suddenly started screaming when I put him to bed, previously he just cried a bit and then settled. He now screams so loudly that the monitor is constantly in the red. First night we picked him up and brought him downstairs and then he just smiled at us, so did not really seem as if there was anything wrong. Has anyone else had this happen and if so what did you do and what worked, as need to go to bed at some point and can't keep doing this.