its about shots
a tetanus shot is to keep you from getting tetanus otherwise know as lock jaw so you wont feel anything except good health
The duration of your shot's symptoms will always be different. for me I usually feel achy and almost like I have the flu for a couple of days. Also, the injection site becomes a little red, hard, sensitive and swollen. This quickly disappears within two to three days. But, the site will be continue to be hard and maybe a little bit sensitive for a week.
But that's just me. If you get severely sick then you need to see your doctor immediately.