Vegetarian throwing up meat?!

Patient: I became a vegetarian 2 months ago. Have been having a constant pain in my left kidney area. and an occasional pain on my left side upper abdomen area. I threw up today and it looked like a big chunk of meat! very concerned since i’ve had no meat for 2 months! what could be going on and is it serious?

Symptoms: pain upper left quadrant, left flank pain, pain in stomach after eating. fatigue.