me and my wife both quit caffeine at same time. She had terrible headaches for about 10 days....I had no headaches but started having weird leg pains. At first I didn't connect it to caffeine withdrawal but some internet searches turned it up.

I suppose its the same cause of headaches: vascular expansion. Caffeine causes your blood vessels to constrict and when there is no caffeine your body initially has trouble regulating dilation naturally, which causes expanded blood vessels which put pressure on surrounding nerves.

It lasted about 8 or so days for me. literally felt I pulled a hamstring.