Getting mri for face pain suspected atypical tn but getting headaches and fatigue. temple is very painful to touch with some swelling. another cause?

Maybe: There is an autoimmune disease known as temporal arteritis, or giant-cell arteritis, which is unusual in people <70 and exceedingly rare in people <50, but occasional cases in younger people have been reported. With signs and symptoms like yours, it would be prudent to rule it out. The MRI, if the right part of the head is imaged, may actually be helpful.