1. A fever over 100.4 degrees Fahrenheit.
2. Lethargy, difficulty waking and feeding
3. Cyanosis, which is blueness around his lips during feeding or at any other time
4. Diarrhea, continuing for more than 24 hours. If the diarrhea is accompanied by decreased urination, however, contact your provider immediately. Do remember that baby's stools are naturally loose.
5. Constipation, meaning hard, pellet-like stools
6. Loss of appetite. If your baby refuses 2 or more feedings, she may not be feeling well.
7. Vomiting, other than "spitting up" or "wet burps"
8. Uncontrollable crying
9. Breathing problems, like uneven or difficult breathing or the absence of breathing for more than 15 seconds
10. Jaundice, with yellow skin or eyes, that shows up after the first week, or darker yellow than when the baby was discharged from the hospital
11. Discharge from the ears, eyes, mouth, or genitals
12. Heavy bleeding or foul-smelling discharge oozing from around the navel after the umbilical cord has fallen off, or around the circumcision area
13. No wet diapers for 24 hours

In fact you should feel free to contact your provider with any questions or concerns after your baby is born.