Sinus Medication Solution

I am constantly have issues with a post nasal drip cough and sinus headaches. Headaches get worse after exercise and being outdoors for long periods of time. My dr has prescribed Zithromax for my cough, and I have used nasal sprays for the sinus pressure but the results are short term relief at best.

Im wondering if its time to see a specialist of if theres any other treatments I can try.