I know this is going to sound like no help, but honestly, you will just know. Let me ask you this - when your SO comes in the room, even before he says anything, can you tell that he's in a bad mood, or if he's really happy? Do you know when your friends are feeling down but are trying to hide it?
You probably know these things because you know them, so you pick up on the signs that things aren't right with them. It will be the same with your baby. You're going to get to know your baby, and you're going to be able to pick up on the signs. Is their nose running a lot? Are they coughing? Are they more fussy than usual? Do they have a fever (lol - and a thermometer will tell you this - you don't even have to guess) All of these things will help you. Plus, as the pp said, go to the appts, and talk to your baby's Dr, and you'll learn.
at 10:34 PM on Sep. 21, 2009