Do you know how high your temperature went and is it still high? Has the headache gone now?
Basically if you're getting those kind of side effects beyond about 7-10 days, and they aren't improving, you should be asking your GP about them. They may have some other questions to ask about those/other symptoms, or advice to give in what to do, or it might be not vaccine related at all.
Things like itchiness near the vaccine site (and sometimes beyond) last longer in a few people. But most of the other stuff fades faster.
No idea how high my temp was but as soon as I wake up it's gonna anyway. It happens when I have the flu jab too, it's normal (I think??) For me at leastm