Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services for trouble breathing, blue or grey skin, unusual unresponsiveness, severe swelling with distress, major bleeding, or a wound that opens and exposes tissue or organs.
After discharge, contact the surgical team promptly for poor feeding, repeated vomiting, increasing pain, fewer wet diapers, new abdominal swelling, wound redness, drainage, bleeding, or a temperature at or above the threshold in your discharge instructions.
Green vomit needs urgent assessment.
Questions about dressings, feeding progression, scar appearance, and appointment timing can usually wait for routine office hours unless there is a sudden change.
The article also says
While your baby is in hospital, tell the bedside team about any new change.
Every sign above is quoted from the sofidex article on Omphalocele repair. If you are not sure, err upward — it is always reasonable to be checked.