As you are having abdominal pain for 4 days now; it is certainly not due to worms/constipation.
There are many reasons for abdominal pain.
Abdominal pain is caused by inflammation (for example, appendicitis, diverticulitis
, colitis ), by stretching or distention of an organ (for example, obstruction of the intestine, blockage of a bile duct by gallstones, swelling of the liver with hepatitis), or by loss of the supply of blood to an organ (for example, ischemic colitis
There are certain red flags in which case you need to consult doctor
Fever, Inability to keep food down for several days, Inability to pass stool, especially if you are also vomiting, Vomiting blood, Bloody stools,Difficulty breathing
, Painful or unusually frequent urination
, Tender abdomen.
So keep eye on red flags as mentioned above.
Consult surgeon for physical examination and imaging [USG abdomen/CT abdomen].