Chlamydia? Latent? False-Positive?

Hi, I have recently been diagnosed with Chlamydia.  I have only had 3 sexual partners including my current partner.  I have been with him for 3 years and did not have sex with anyone the year before I met him.  So technically I have only had sexual relations with him for the past four years.  We went to his doctor today because he recently got tested for everything, too.  His doctor went over his results again and they were all negative.  We both got retested with his doctor and are waiting for the results.  I am hoping it is a false-positive.  He denies having had sexual relations with anyone besides me during our relationship.  He has only had one previous partner.  I am not sure what is going on.  Please help.  I do not know what to believe and do not know how I could have gotten this if he didn't give it to me.  Is it possible that my ex from four years ago gave it to me or his ex from 3 1/2  years ago gave it to him? Why would his results be negative if I supposedly have it and we have had an active sexual relationship?  Thank you.