What can cause early satiety, nausea, and stomach pain (upper left) if abdominal ultrasound and chest ct were normal?

Many things: These symptoms may indicate a problem with how the stomach empties and can occur for many reasons. Abdominal ultrasound would not even visualize the stomach. Chest ct may image a portion of the stomach, but would easily miss both anatomic and functional stomach pathology. A GI specialist may be able to determine the appropriate workup (e.g., gastric emptying study, barium swallow, manometry).