Intussusception: This is the most likely diagnosis given the presentation, as it is a common cause of intestinal obstruction in children, characterized by the telescoping of one segment of intestine into another, leading to bowel ischemia and potentially necrosis if not promptly treated.

Gastroenteritis: Inflammation of the gastrointestinal tract, often due to viral or bacterial infections, can cause symptoms similar to intussusception, such as abdominal pain and vomiting.
Incarcerated hernia: A hernia that becomes trapped and cannot be pushed back into the abdomen can cause severe pain and obstruction, mimicking intussusception.
Volvulus: A condition where the intestine twists around itself and the mesentery that supports it, cutting off blood flow, can present with similar symptoms of abdominal pain and vomiting.

Appendicitis: Although the presentation can differ, appendicitis is a critical diagnosis not to miss due to the risk of perforation and peritonitis, which can be life-threatening.
Mesenteric thrombosis: A blood clot in one of the major arteries that supply blood to the intestine can cause severe abdominal pain and ischemia, leading to necrosis if not promptly treated.
Internal hernia: A rare condition where there is protrusion of intestine through a defect within the peritoneal cavity, which can cause obstruction and ischemia.

Meckel's diverticulum: A congenital anomaly of the small intestine that can cause obstruction, bleeding, or inflammation, and might mimic intussusception in its presentation.
Intestinal lymphoma: A rare tumor of the immune system in the intestine, which can cause obstruction or intussusception.
Ovarian torsion: Although more common in females, this condition involves the twisting of the ovary around its ligaments, cutting off blood supply, and can present with acute abdominal pain, potentially mimicking intussusception.