Yes, there could be side effects to Novocain such as:
an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);
chest pain or slow or irregular heartbeats;
dizziness or drowsiness;
anxiety or restlessness;
nausea or vomiting; or
trembling, shaking, or seizures (convulsions).
If you have any reactions you should probably contact your doctor.