My DS is about 13 weeks and with the exception of one top off of formula on Sunday by the grandparents is exclusively breast fed. He hasn't had a bm since Monday. This morning there was a spot off poo on his nappy but that's it. Nappies are wet. He generally eats 6 or 7 times/day is offered both breasts and usually feeds on both. Otherwise he's his normal feisty self. I'm not sure at what point I should really start to get concerned. Ay thoughts/input appreciated.