Can your throat hurt for months from a sinus infection?

I get seasonal allergies throughout the year and this year about two months ago, I started getting really sick, with a runny nose, sore throat, and very congested. I went to the Dr. and he gave me some antibiotics - Amoxillin 250 mg. It didn't work so I went back, because I was still sick. So, he then gave me a steroid called medrol and an allergy medication called Singulair. About two weeks later, I was still with a runny nose, congested and my throat was killing me at this point. So, I went back another time and he took some X-rays which proved that my facial cavities were stuffed and he figured it was a sinus infection. This time around, he gave me another antibiotic which name I can't remember, but it was only 250mg. He also gave me Zyrtek and a nasal spray to decongest. My congestion cleared up and so did the nose drip, but my throat is still bothering me and at this point I developed a cough from the irritation, I figured. So, I decided to go to a Ear Nose and Throat Dr. - a specialist in the matter. She said my sinuses were swollen and my throat did look a little red. She then gave me Levaquin 500mg. I've been on it for about five days along with taking Claritin and Singulair both and my throat still hurts... how long does it take for it to go away? Does that mean the antibiotic is not working? Or do I have to wait a while before it takes effect? I'm not congested anymore nor do I have mucosity, but my throat hurts very much, and my cough won't go away. Please help me!!! My house is becoming a pharmacy with so much medication.