For the past 3 weeks or so, I have been experiencing a very uncomfortable feeling behind my eyes, in the temple region, cheeks, teeth, and the back of my head (top of the neck). Although this hasn't been debilitating, it's been a real annoyance. I get bouts of "fogginess" and have slight vision issues. It feels like this is coming from the sinuses, however, I'm not congested. Any thoughts?