Shaking after flu jab - normal reaction?

[Pinchypants]

Hiya,
My dad (63) had his flu and pneumonia jab yesterday and apparently can't stop shaking today. He's the polar opposite of a hypocondriac so if he's even mentioned it he must feel really crap and be worried. I've googled side effects but can't get any definitive answer on whether a shaky fever is a likely side effect or if he's just been incubating a virus for a while anyway and it's coincidence. Any ideas?
Thanks!
Pinchy

My dad was really poorly last year after this. he'd had the flu jab for many years before, but this was the first time with the pneumo one combined. He was ill for about 4 days with high temp, shaking, cold and cough. Swore he'd never have it again and hasn't htis year.

HTH