Hey Bataar, I also have had trouble with a screaming baby. They can really tug at your emotions can't they? I think that this is why maternal instincts are so naturally strong with women. It is almost on a psychic level for them. Perhaps I can relate to the pain that the baby is in because it has been such a norm for me in life.
Now, however, I can pretty much tune out a crying baby being that it isn't mine and I am not responsible for comforting it.
I saw an Oprah special where one lady was so in tune with her baby that it didn't really cry that often, or loudly, because she knew what it wanted from close and constant observation of the variety of cries. If a parent can meet a baby's needs when it cries as a newborn, it will cry less and less as it grows up, and won't be tempted to cry just to get what it wants. In essence, it will only use crying when it NEEDS something rather than out of frustration because you aren't meeting its needs. Here is a site that is very valuable, in my opinion.
http://hubpages.com/hub/Why_is_my_baby_crying