My son is 3 weeks old and has recently begun to decline as far as
breast feeding goes. He will get hungry and root and cry etc but once
I put him to my breast he will open his mouth very wide and shake his
head all over the place, refusing to latch and suck. Once he does
latch, he will then take one or both hands and push my nipple out of
his mouth and repeat the whole head shaking process over again. I have
tried swaddling him to prevent his hands from getting in the way but
he just gets mad and arches his back and cries so I'm actually better
off fending off his little hands from getting in the way because at
least he's in a position to latch on.

I don't know what brought this on, but until now he has eaten well and
we could generally get the job done and have him content within about
30 mins. Now it is taking upwards of 2 hours per feeding and I'm not
even sure that he is full as much as worn out by the end of it because
at times he will wake up screaming an hour later and we will repeat
the whole process over again. I spent 4 hours going through this last
night (2 two hour feeding sessions) and today all he seems to want to
do is nibble a bit and sleep. I worry that on top of everything else
he's starting to confuse days and nights.

Any experienced moms out there who can offer some advice? I'm
exhausted and extremely frustrated. He's been such a mellow baby and a
good eater until now. This has really caught me off guard.

Have a lactation consultant in your area come and watch your technique--ASAP. Its often a matter of positioning or you may have thrush...etc. If a baby is not positioned exactly right, they often won't latch on. My son was the same age when he quit nursing. He was doing exactly what you describe. If he wasn't in the PERFECT position, it was a disaster. I was so frustrated. The lactation consultants can really help. They know their stuff. I say do it right away because your baby may not be getting enough to eat in the mean time.

In the end, I quit nursing altogether--but my now 3 and a half month old only gets breast milk. I pump and give it to him in a bottle. This way I know how much he is getting.

there are at least a hundred gazillion reasons why your son would be refusing your breast right now..... a change in your diet or taking certain vitamins could change the way your milk tastes. if you have a strong let down, it might be coming at him too fast for him to swallow. if it's coming out too slowly, it might just be frustrating for him because he is having to work too hard to eat..... these are just the first things that came to mind....

my one piece of advice is to watch for any green poops. this would indicate a fore/hind milk imbalance. it's the one thing i have to post for anyone having breast feeding issues because nobody told me about it! if he's getting too much foremilk, it can cause a lactose buildup in his little system and cause a lot of abdominal pain and discomfort, making eating horribly uncomfortable and painful. my second baby went through this and i had to find out about it online because her doctors just said she was colicy or had reflux!

anyway...... just my two cents..... hope things get better for you!

Please consider acid reflux.
Your description sounds EXACLTY like my agony when my child was behaving like this.For nearly 2 months no one listened (pediatrician, GP etc), my br%%sts got ruined and chewed upon since my DD would be very hungry, start to suckle but the pain becoz of the acid reflux would start as soon as the milk would go into her and she'd start screaming and not want to nurse anymore. I would be upset since just as let down would beging she'd refuse and I'd have to pump. It was very agonising on many fronts.. Please have your pediatrician check for acid reflux. It starts showing up a few weeks after birth.