Do you feel like something is wrong with your body, even when not in a flare?

Hi, all. So lately I haven't been feeling good. If you check my history you will find I've been having gastritis, or that's what my doctors say. But the thing is, I don't feel like is gastritis, even tho the symptoms are alike (nausea, pain, heartburn). I feel like the symptoms are a product of inflammation, specially because the pentoprazole and other antacids aren't helping, and after a few days I start feeling a bit worse. However, my inflammation markers are all good, and the cal protecting was also fine, and my GI won't do a colonoscopy. On the other side the only thing that came from an endoscopy, were polyps and duodenitis. Could all this be inflammation related to UC, even tho my markers are fine?