I have had headaches every day for almost a month (with no history of headaches) post wisdom tooth surgery. what are the possible causes of this?

? Extractions: Sometimes 3rd molar extractions require pretty violent pulling on the neck and jaws. If you were asleep for the extractions, this may have occurred. You could have a mild neck strain or TMJ pain. Tmj usually has pain on chewing or clicking when you open your mouth. Check with your dentist. You may need to get some physical therapy treatments..

Muscle pain: You may have a tension type headache that may have been triggered by having your mouth held open for a while with the extraction. I would suggest seeing a medical specialist in headaches or dentist who specializes in facial pain if your dentist cannot help you.