Oh, I feel for you! I think I've got a sinus infection, too! I have been dying here, but didn't think it could be because I am not congested, but tonight I know that's what it is. My face (sinuses) are killing me and pain relievers aren't helping much. I wish I had gone in to the doctor.
Now I have to go through the weekend in pain...
I hope you get feeling better soon! Sinus infections can really last a long time. Sounds like you need to try a different antibiotic.