Befuddled symptoms and conditions

I recently took the single dose liquid Z-Pak for what was supposed to be bronchitis. Three days later, I have a full-fledged sinus infection and painful, ringing in my ears. The stuff also seems to have given me horrible dreams, and I can sleep for only about and hour and a half at a time. During the time I'm awake, i'm so befuddled I can barely function. How long does it take for this stuff to get out of your system?