@theache- Welcome to Mayo Connect!
As you can see many people who had their gallbladders removed, report a variety of problems after surgery. I have not seen a complaint like yours, with severe headaches. It probably has no connection to the surgery. The right specialist for you now would be the Neurologist. There are very many causes of headaches Let's hope the Neurologist have some answers for you. Please get back to us with any new information, please!
I hope that there are other members that can share experiences.