I have, I usually get one or two nastys infections a year :P ... are you sure the first anti-biotic cleaed up the infection? If so, maybe it's just taking a while for everything to drain still. Make sure you drinking a lot of fluids...hot tea is very soothing, I'd try that, to help loosen stuff up more, and get it all out.

How long have you had these symptoms for? Maybe you need to call your doctor and get put back on another anti-biotic?