More than likely you just received a tetanus shot as Tdap, Boostix is expensive. It is recommended that everyone between the ages of 11-64 receive i tetanus pertussis booster. Then a tetanus booster every 1- yrs unless you get a serious cut. If you are not sure if you received a combination shot, you should get a tdap. any side effects you experience is 10x less than the problems that tetanus or pertussis can cause. I find it amazing that employers don't offer the shots to employees so that they know your dates. ( I worked in health care and ran an immunization clinic and none of us could get a free shot until we had an outbreak in the county).