My 3-week-old is not sleeping much - definitely less than the ballpark hours I have read about. This has just been in the past week. I was attributing it to the heatwave and need for constant feeding to stay hydrated, but today is much cooler and he is feeding less but not sleeping much. Think may have been windy and got overtired. In sling right now and that has sent him off for the moment. Anyone else experienced newborns who sleep little - tips and watch-outs welcome...