Hi S.,
Are you breast feeding or using formula? The reason I ask is because both of my kids had difficulty processing the iron in the powdered formula which my pediatrician said is quite common. As a result, we had to use the concentrated (more expensive!) formula.
My son was particularly fussy and difficult to burp. Have you tried infant massage? This technique is said to help with digestion:
1) Lay your baby on his back.
2) Starting in the middle of his chest with both hands move up and around his chest and then down towards his stomach making the shape of a heart (wish I could draw a picture to demonstrate). 3) Use gentle strokes and repeat several times.
Good luck to you :)
J. Urbane, The Mentor Mom
www.thementormom.com