Last 48 hours i've had increasedmuscle spasms all over my body/immense pain in my neck. cut myself with a kitchen knife puncture wound last week but haven't had tetanus shot in 12 years should i worry?

Yes: While the anecdotal time frame is to get a tetanus immunization every 10 years there is no accurate telling that your immunization is still effective. Your symptoms and the length of time since your injury could be the early symptoms of tetanus. I would advise you to see an infectious disease specialist or a neurologist asap.

You have gotten many: Answers to your dilemma. Someone told you definitively if you had tetanus you would be dead by now. You are however suffering. I would recommend that you see your family doctor or go to the emergency room to find out what the cause is. It is apparently unlikely to be tetanus but something is going on and you are suffering badly so i recommend you return to the emergency room but have them evaluate you for your symptoms and don't even mention the word tetanus. There maybe something entirely different going on. You deserve to have your mind put at ease regarding what it is that is causing this intense suffering.If it turns out that nothing is physically wrong, then please get into psychotherapy to deal with your health anxiety. See a psychiatrist as well. Best wishes.