Ok, I find if I listen to the start of the cry and the actual pitch, I can work out what he wants. If it starts out with a wimper and builds quickly, It's usually food or cuddles. If it starts out loud and screaming, it's pain in tummy or wet/poopy nappy. If all else fails, I find if I hold my little man snuggly over my heart, he will settle down quite quickly. At this stage, their needs and wants are very basic. Try not to pass them around too much and wrapping is a good idea if they are overtired so they don't wake themselves when they wave their arms etc....
Not much help, but that is what I have found....