Unfortunately, I cannot offer a diagnosis based simply upon the description that you have provided. There are multiple potential causes of early satiety (feeling full very quickly when eating), and so I would recommend that you be referred to a GI doctor, especially if you are also losing weight.
You may require that a scope be placed into your stomach (through your mouth) to assess your esophagus, stomach, and duodenum (first part of the small intestine).
Sincerely/ Robert A. Wascher, MD, FACS
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