Medic here-
describe the bite - the feverish, achy part could just be a cold. without a full description of the bite area - is it inflamed, dimpled, necrotic, hot to the touch, is there a center pustule, has it grown since the initial bite, yada yada yada... it's tough to say anything.
Max hit it on the head - when in doubt wit harachnids - see a doctor.
A Brown Rercluse bite can be treated easily early on - Tetracycline and good wound care... if you wait, not only tetracycline, but possible fasciotomies, definite debridement (and yes, some places are back to using maggots for that), and some of the side effects - like huge scars, muscle loss,and circulatory impairment are not fun.
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