Tetanus symptoms result from a toxin produced by tetanus bacteria. Symptoms often begin around a week after infection. But this may range from three days to three weeks or even longer. The most common symptom is a stiff jaw, which can become locked.. This is how the disease came to be called lockjaw. Symptoms of tetanus may include: 1  Headache. 2  Muscle stiffness, starting in the jaw, then the neck and the arms, legs, or abdomen. 3  Trouble swallowing. 4  Restlessness and irritability. 5  Sweating and fever. 6  Palpitations and high blood pressure.