An MMR Titer is a blood test that checks your antibody titer levels to Measles, Mumps and Rubella. It is run in a laboratory. A titer test is not an injection, shot, or vaccination. An antibody is a component of the immune system.
If you're an adult, get a Td (tetanus and diphtheria) booster shot every 10 years to stay protected. Since some people may lose the protective antibody levels after 5 years, a booster vaccination is recommended if you get a deep, contaminated wound and haven't had a vaccination in more than 5 years.
The first immunizations for tetanus, diphtheria and pertussis (the DTaP shots) start when kids are only 2 months old (definitely no earlier than 6 weeks). Adolescents get a booster Tdap shot at around 11-12 years (if they miss it, it's OK for them to get Tdap between 13-18 years). Adults should get a Tdap shot for one of their tetanus boosters. The others will all be Td shots. Remember, you need a tetanus booster every 10 years. If you are over 65 years old you might not need the Tdap shot, but you can still get one. You should talk to your doctor.