Element is right... it sounds serious at this point. I usually put off going to a doctor as long as possible. I even skip it when I know I have an infection- I give my body a chance to fight it before going for antibiotics. But, you've been sick for at least six weeks now, and there could be some kind of serious involvement that requires antibiotics and/ or steroids to treat. (Or something else entirely.) Regardless, it's time for a doctor. Good luck.
I don't think there's something called a sinus flu. It could easily be a sinus infection, which generally does not go away on its own. If you're having difficulty breathing, then you definitely need to see a doctor STAT.
