Hi
My little girl is now 5 and a half weeks and I have also been having feeding problems, I am breastfeeding, but feeds are also regular and she fusses and fights during feeds, even though she is hungry.
We have tried everything, increasing my milk supply, getting her to be more effective at the boob, treating thrush, taking her to a chiropractor and I too am at my wits ends, She does drink quite a bit, but fights during the feed so it takes a long time.
We went to the chiropractor last week, as we were told sometimes new borns need thier spines etc aligned as this can pinch nerves in the spine and cause tummy prolems.
The chiro said she may have refulx so we took her to see our GP ( Pead is away at the moment, going to see him next week) and they have given us an antacid to disolve in some milk once a day, it seemed to help a bit with feeds over the weekend, I have been told it takes a week to work, perhaps your little one has reflux
There are other things you can do as well, feed him upright, make sure his cot is inclined and hold him upright for at least 20 minutes after the feed.
Good luck, I am hoping we are on the right track now, cause I am about to give up on this whole breastfeeding thing