Rhonda ~
I can't answer your question with any degree of certainty but I know that MRI scans do not emit radiation. However, CT scans do - quite a bit, as I understand it. Whether the gadolinium you received or, perhaps, the CT scan are a cause of your feeling unwell is a question that will likely remain unknowable. I can state that I've had many MRI scans, all with the gadolinium contrast agent and a few CT scans, too, and never felt ill afterward. Still, that is just one person's experience and we know that as individuals, our bodies will react somewhat differently to radiation and even gadolinium. Because the answer is going to be elusive, at best, I would guess that flu or a cold along with the stress that lowers our immune systems effectiveness is most likely the culprit. Whatever the actual cause of your symptoms, I hope you feel better, soon.
Jim