What may be causing my neck pain?

About a month ago, I had bronchitis that quickly turned into walking pneumonia. I am on the 3rd antibiotic in a month and I just don't feel right. Last week I went to the doctor and he took a chest x-ray that showed no infection in my chest, but my WBC count was up. That's when he prescribed me my 3rd antibiotic. For 6 days now, I have had swollen glands and a sore neck, especially when I put my head all the way back. There is always this dull ache though at the base of my head. I don't know why these doctors keep prescribing antibiotics, because I know whatever it is, it's viral. I just don't know what is causing this annoying pain in the neck. I haven't been running a fever or anything else. Does anyone have any ideas? I feel sluggish all the time and have felt that way since I was diagnosed with my bronchitis.