It is possible that post-cholecystectomy syndrome (PCS) could be causing your ongoing symptoms, even after having your gallbladder removed. This syndrome can lead to similar symptoms such as cramping pain under the ribs, nausea, and vomiting. Keeping a detailed journal of your diet, activities, and emotional state over the next few weeks could help identify any triggers or patterns causing these symptoms. If no clear cause is found, it might be advisable to consult with a healthcare professional for further evaluation and management.