Could a hole in the tooth on right side cause severe headaches that side?

While a hole (also called a cavity) in the tooth can potentially lead to pain and sensitivity, it is unlikely to be the primary cause of severe headaches. Headaches can arise from various underlying medical conditions, and their severity and nature should be evaluated by a medical professional. Headaches that persist or are accompanied by additional symptoms require proper diagnosis and management to determine the exact cause and ensure appropriate treatment.