My first was breastfeed and was always constipated, its good to remember that what ever you eat, baby gets too.. if you can cope with eating something like prunes or licorice this may help. Prune juice is really good, and was my saving grace. I dont like to use bottled prune juice as it is far too strong and full of presertives, if you put 1-5 prunes in a pot of water, and let it boil until the water is just stained brown, its a great remedy, the darker the water the stronger the brew, (it just depends how constipated bubs is)it can be kept in the fridge for a few days too!
Camomile tea is ok, but more so for relaxation, you can get the whole flowers (dried) a heaped teaspoon will be plenty for a large bottle, just steep it until the water is slightly coloured yellow. and strain with a FINE strainer cos it does get a few floaters in it!!
Good luck, hope you get some success!!!
Sian 6yo G + 3mth bubs