Open cut somewhat skin was red. I stepped on rusty steps do I have to worry about tetanus? Or split skin open cut with red inside hurts bad

Yes and No. Yes... one can get a Tdap shot if the person is an adult and hasn't gotten a Td or Tdap shot in the last 10 years, regardless of the current incident. No... if the person's tetanus shot within the past 10 years was Td or Tdap, there is no special worry about tetanus in such scenarios.