I stepped on a rusty nail 3 days ago and the wound was jush shallow. i did not have any tetanus shot since i was born. am i tetanus positive?

Not protected: Suggest to get tetanus shot, preferably tdap.

Maybe,maybe not: You'll know within a few days if you will get tetanus from this exposure.The germs quietly fester in the wound and produce the toxin. Your initial wound care may have washed away any spores so you may be lucky.Even if it is late, consider this a wake up call.You ought to get caught up with any of your delayed immunizations before your luck runs out.

Have it evaluated: Deep puncture wounds can be potentially dangerous as one may develop tetanus, or a number of other types of deep infections. If the wound was deep enough they may lead to bone infections. You may need periodic debridement of you wound to remove any unhealthy tissue.