You could have a test called the gen-probe, which looks for DNA of chlamydia, but its still possible that it would mask it. The gen-probe is the most sensitive of them, so you'd have the best luck.
However, if your bf is infected, and you've had unprotected sex with him, then chances are really good that you have been. You could just treat it as if you have been, for safety's sake, if your doctors are ok with that. This is something I would be talking to your doctors about.
AJ
if dapsone is capable of masking the infection what other ways are there to know if have been infected?
Steve -
It usually is sent to a lab, where they test the specimen, then have to send the results back.
Perhaps your clinic has a lab on-site, but otherwise you wouldn't get results in 30 min. You might want to check. Some clinics have labs where they can look for white blood cells in your urine, which can indicate chlamydia, but that isn't a chlamydia test by itself.
AJ
It might prevent it, or it might mask it so you test negative.
My thought would be to talk to your doctor about treating you anyway, since you can't risk an infection (your boyfriend should know this, right?) If you can't take zithromax, you can ask for doxycycline 100 mg twice a day for 7 days. There are others that are possible treatments. Have your doc look at the CDC STD Treatment Guidelines and he can decide which one would work best for you.
AJ