If I was put on antibiotics two days ago for an enlarged appendix, but not infected. And the pain is not getting any better, what should I do?

Family Doctor. I think this is the tenth question you have asked us, strangers on the internet, but it appears you are not getting the right help in person. You have a family doctor. This professional should be consulted and aware of your problem so that these ongoing questions are managed appropriately. You do not need to go back to the ER. You need to see your family doctor.
How long . have you been on the antibiotic? If the pain persists, go to the emergency room and get another evaluation. .