I had a chest x ray and it showed a shadow on right lung. Now doctor wants a ct scan done. I am confused as to why the need for ct and no more meds.

Sometimes they find something different when they do tests. What you presented was Pneumonia, but when they got to diagnose it, it was something completely different. Could be a good thing, could be bad. Good luck.

Chest x-rays are really intended to show bones... a few other things barely make it in like shadows but they are cheap and quick... CT scans show soft tissue in detail... but tend to be expensive and take significantly longer and rarely can be done in house. It's a step towards justifying the more expensive procedure.

A CT scan will show a clearer picture of what's causing the shadow. Doctors rarely order tests that aren't necessary to diagnose. I'd err on the side of caution and get the CT scan done.