So our 10-day old is starting to get the hang of breastfeeding, and showing all good signs so far: good diaper output, weight gain (although still a little on the low side). Normally he'll be hungry every 3 hours or so at the most. So today he feeds at 2pm, then falls asleep. It gets to about 6pm, and my wife and figure we should wake him. We start to wake him up, and he's not showing any signs he's hungry (no rooting, smacking his lips, etc.). We try to feed him anyway just to see, but it's pretty clear he's not hungry (starts fussing at the breast). He gets pretty upset, so I swaddle him and rock him a little, and he goes back to sleep! It's now 7:30pm, 5.5 hours since his last feeding. I don't think he's ever gone this long before, so, I ask you, is this normal, or should I be concerned about this?