I Have Been Vomiting For 3 Months. Went To The

I have been vomiting for 3 months. Went to the ER and was told I had colitis after a CT scan. Given antibiotics. Pain started getting really bad in abdomen when on antibiotics. Finished antibiotics. Pain remains. Have not had a bowel movement in 3 weeks (since right after finishing antibiotics). Pain in abdomen generally comes in waves and is across the whole abdomen generally with a few specific pain points.