I forgot one thing you might want to rule out, sorry.
Closed angle glaucoma can cause headaches (as well as other symptoms).
It is not common but something you want to rule out because if detected early is correctable; if not you go blind. It can be similar to a sinus headache.
You can rule it out by having your intra ocular pressure measured by your friendly optometrist.
RE: How Do You Get Rid Of Headaches? I Need Some Advice!