just wanted to say at trying times such as these try to turn a blind eye to anything that doesn't have to be done.... housework, obligations etc.... just do the bare minimum.... it is just a phase and will soon run its course i am sure.... i had a baby like that from birth with my first born and it was hard work, she turned into a delightful toddler.... i wished i had of taken her to a chiro/osteopath for her neck which i now believe was causing her great pain, but since your little one has been okay since birth but is now becoming distressed, i don't think it would be that sort of thing... just try to get thru it the best you can, and if it means curling up on the couch nursing him while you also doze, then do it.... you will never get time again to do that sort of thing, as the next baby you have (if you have another) you will have an older child to run after, so revel in the luxury of being able to put your feet up with him and ignore the things that don't have to be done....
good luck xxx i'm sure i will be there in a few months, my little one is 2 months and doesn't sleep during the day, the evenings are my sane time, hoping it stays that way!!