Acute pancreatitis (AP) is a common medical condition with a wide variety of etiologies. One of the common but frequently undetected causes of acute pancreatitis is microlithiasis, which can appear as biliary "sludge" in the gallbladder on imaging. While a broad workup should be initiated, endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for the diagnosis of microlithiasis. In this case, we present a severe presentation of acute pancreatitis in a teenager within the postpartum period. A 19-year-old woman presented with severe 10 out of 10 right upper quadrant (RUQ) pain with episodes of nausea that radiated to her back. She had no history of chronic alcoholism, illicit drug use, or over-the-counter supplement use, and no familial history of autoimmune disease, or pancreatitis. The patient was diagnosed with necrotizing acute pancreatitis with gallbladder "sludge" using contrast-enhanced computed tomography (CT) and magnetic resonance cholangiopancreatography (MRCP). She followed up with gastroenterology and had a great clinical recovery. Therefore, it is important to consider acute pancreatitis in patients with idiopathic pancreatitis in their postpartum period as they are prone to forming gallbladder "sludge" which can precipitate and cause a variation in gallbladder pancreatitis which can be difficult to detect on imaging.