First, you should take care of the wound with thorough cleaning.
As to the tetanus, if your immunizations are not up to date, then you should contact your physician. As to what exactly you need, depends upon what tetamus immunizations you have had (types and how many of the series you have had).
Most adolescents are up to date on their "shots", as they need them to go to most schools. If you are unsure of what you have had, you should contact your physician or go to an acute care facility.