Here are the signs and symptoms that the tooth infection has spread: Headache and dizziness. You may be feeling unwell, aside from tooth pain. High fever. Fever is often your body’s response to infection. You may also experience chills, skin flushing, or sweating. Swelling. Swelling can make swallowing, breathing, and fully opening your mouth difficult. Dehydration. A tooth abscess can cause dehydration due to the increased need for fluids to fight the infection. Dehydration can lead to darker urine, confusion, or a reduction in the frequency of urination. Fast heart rate. In some cases, an infection may be accompanied by an increased heart and breathing rate.