I had a chlamydia urine test 3 days after 'potential' exposure at my local clinic. the results are negative. how accurate is this test?

Very: There is no test that is 100% accurate. All tests have some false positives and some false negatives but the urine test for chlamydia is considered to be very accurate. If it is negative you don't need to worry but this should remind you to use condoms every time to decrease the risk of STDs unless you are in a mutually monogamous relationship. Hope this helps.

Good if done right: It's a good test if done right. Unlike urine samples for bacterial infection, this test should be done on the first urine to leave the bladder (not a 'clean catch'). If there are symptoms of vaginal/uterine infection, then further testing would be warranted.