What Do Back Pain, Belching And Green Colored Stool Indicate?

Hi I m a 32 year old female with history of gastritis and diverticulosis. I also have rheumatoid arthritis. Last week On Wednesday I had an EGD and now I have sharp back pain, gas/benching, green stool every day. I asked the Gastroenterologist today if they pushed the scope into my esophagus up against my back during the procedure and he said no that maybe I injured myself and asked me to get a CT scan and blood tests. I m worried because my upper back hurts when I swallow food or just drink water. I ve had 3 endoscopies before and never had this happen. Please provide any feedback about what this could indicate. Thank you!