Your tetanus dose from this May already protects you well, even for a wound from a rusty object. That protection lasts years, not months. You don't need another dose now.
Next Steps
Clean the cut well with soap and water, and keep it dry and covered for a few days. Not having a childhood vaccination record doesn't matter here, since this year's dose already covers you.
Health Tips
Herpes doesn't weaken your tetanus protection. Watch for redness, swelling, oozing, fever or jaw stiffness at the wound site. If any of these appear, see a general physician promptly.