Also will link your old thread to this one for you.
the best advice for now is to have skin to skin contact with your baby. strip him down to a nappy and you with minimal clothing on top. let him lie on you vertically with his head more or less between your breasts. Spend a couple hours in bed if you are not too tired at the moment, like this and see if he will latch on on his own.
this is called biological nurturing and if you search the archives with this phrase, other related information will come up.
ohmamma - I agree with everyone here. You need to see the midwife today....4 days without poo can be a sign the baby is not breastfeeding effectively or often enough. Formula will undermine your breastfeeding and make you produce less milk. No panic, but you need help to fix this asap.