not relieved with medication associated with vomiting
and pain does require urgent evaluation to rule out sub acute intestinal obstruction
I suppose you were passing flatus.
Again milky white stool means passing of mucus in stool and is not your normal stool.
Kindly check with a doctor to auscultate the abdomen and check for bowel sounds.
Urgent X-Ray abdomen ( Erect )
It is the first and foremost investigation suggested.
In case your X-Ray is not diagnostic then you might need further investigations:
CT scan abdomen.
Rarely Upper Gastrointestinal Endoscopy
might be required.