Hello. Thank you for coming to JustAnswer with your question, and welcome.
When you had stomach ulcers in the past, did you have treatment, and if so, what was it?
Also, do you have any abdominal discomfort at all (where and what type)?
Do you notice more nausea after eating, have you noticed what type of foods cause this?
Your weight loss is not yet what is called "significant", but 33 pounds in 3 months is still quite a bit.
When you had ulcers before, were you tested for H.Pylori? If not, you need this done. It can be tested for with a breath test, or blood test. It is a bacteria that causes stomach ulcers and needs to be treated with an antibiotic.
There are, of course, many other possibilities. Liver, gallbladder, pancreas as well as stomach and intestinal issues can cause these symptoms.
At this point, given that you are actively losing weight and vomiting, you really do need to see a doctor and have some tests done. This is nothing to guess at right now.
In the meantime, try to eat small frequent meals with very little fat.