Two days ago my husband was punched repeatedly, abdomen, and there is a large dark bruise around his navel. what would indicate internal injury?

Bloody stool/urine: Pain greater than what you expect from the injury, nausea vomiting , loss of appetite, rigid/hard abdominal wall, and bleeding from rectum or in urine are signs of internal injury. If you suspect internal damage better to seek doctor evaluation sooner rather than later.

Pain: Worsening pain, abdominal distention and shock (low BP, high heart rate, paleness, dizziness).