Diverticulitis can feel like appendicitis, except you'll generally have pain in the lower-left side of your abdomen, instead of the lower-right side. The pain is usually severe and comes on suddenly, but sometimes you may have mild pain that becomes worse over several days and fluctuates in intensity. You may also have abdominal tenderness, fever, nausea, and constipation or diarrhea.

Less common signs and symptoms of diverticulitis may include:
- Vomiting
- Bloating
- Bleeding from your rectum
- Frequent urination
- Difficulty or pain while urinating