prostate infection

  i am 20 years old and just this week my doctor diagnosed me for a prostate infection.  he said it was "a little bit enlarged."  to get to his diagnosis he searched my testicles for bumps and then did a rectal exam.  i'm wondering, are these tests sufficient in all cases to determine a prostate infection exists?  i mean, isn't there something else that could cause this?  my symptoms include:
  1) frequent urination (some days more than others)
  2) incomplete feeling after urination
  3) after being done urinating, drops come out one at a    time..very very slowly and quit eventually.
  my doctor prescribed bactrim ds for this.  i'm taking pills twice a day for two weeks.  do you think chances are these symptoms will go away with this medication?  what of symptom #3?  i've read posts from different message boards about prostate infections, but i've never heard anyone describe quite what i'm having.  lastly, if two weeks of this medication doesn't work, should the doctor simply put me on more medication or try to see what else is wrong?  ..and should i be worried?
  thanks.
  sincerely,
  dave
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Dear Dave
Prostate infections are infections of the lower urinary tract and are diagnosed by having a positive urine culture.  Other problems can mimic prostatitis and urinary tract infections like passing a kidney stone or bladder tumor.   If your exam, culture, history, symptoms do not fit, or you do not respond to treatment your doctor will be inclined to perform more test to make the diagnosis.  Your can help by being active in your care.  If your urine was sent for culture, call after a few days to see if the antibiotic prescribed covers the organism they grew in culture.  If no organism grew ask your doctor if he still thinks prostatitis is still the correct diagnosis.  If not what is the next step that should be taken to make the correct or reaffirm the current diagnosis?  Perhaps a urodynamic voiding study would be helpful. Post void dribbling of urine is very common.  It is a normal phenomenon.  After voiding  wait while the tablespoon of urine drains out of the urethra before getting dressed. Hope this has provided some more information to stimulate further communication with your doctor.
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