I Am A 59 Year Old Female With No Diagnosis

I am a 59 year old female with no diagnosis of health concerns, except. Panic attacks, which I take 50 milligrams of Zoloft daily.
Lately I have been having a feeling of fullness in stomach, even though I have not over ate. I did eat a cheeseburger, with fries, and did eat it fast. About an hour later (or less) I felt the need to use the bathroom, but did not have diarrhea. I did vomit everything I ate, I did not feel nauseous. And I do not think the food was digested. It was not watery, more of a oatmeal form. This happened on Saturday night. I ate lightly all day yesterday (Sunday). Today, I woke up feeling very full and after a walk, did feel hungry, so I ate cottage cheese with pineapple. Now I feel stuffed again. What could be causing my symptoms.