Tetanus shot & stitches

So last night my boyfriend cut his finger while using a scraper blade trying to scrape something off. And we went to Patient First and he got 3 stitches and a tetanus shot. This evening he said he started to get a headache and sore throat. And now he has a migraine. Does this have anything to do with the shot? Or is it just coincidence and that he just may be coming down with something?