2 weeks? that's quite a long time... and any sane parent would be concerned when something like this happens. My youngest (9 months old now) had the same situation when he was slightly younger than yours, exclusively breast-feeding also. After a week (and after visits to the doctor also saying it was normal), I sought advice from my parenting forum since of course, what the doctor says and what you as a parent feel about your baby do not always go hand in hand. So I tried the solutions offered, which ranged from just giving him a bit of fruit juice (did not work) to this---> take a q-tip, dab the tip with some vaseline and then insert the q-tip (just the tip) into your baby's rear-end and gently use the q-tip to massage the entrance of the anus, twirl it round, which is intended to make the baby reflexively move his rectal muscles (okay the terms here may not be correct from memory, but serves as a guide) and should result in him pooping. Keep doing it, mileage varies from baby to baby... and guess what, it works every time. And boy does it work... be prepared for a deluge of poop once it happens... not pretty at all Mine took from a couple of minutes to around 5 minutes The wife only had to use it three times over the next two weeks i guess, and the baby seems none the wiser, and both parents can breathe easy.