Positive for chlamydia boyfriend negative.false positive or false negative?

[NicknameWill]

I lost my virginity to my boyfriend and have only had sex with him. I went in for my first Pap smear in April 2016 and also got tested for stds. About a week later I got a call from the doctor he said I had get another Pap smear and also said I tested positive for chlamydia. I was really upset because my immediate thought was that my boyfriend cheated on me on a recent trip home. He swore he didn't I believed/believe him and I told him to get tested and treated. His result came back negative so he didn't get treated and he suspected I lied about being a virgin or cheated on him which is not true. I have never done any type of sexual act besides kissing before I was with him. I got treated and went back a month later to make sure I didn't get it again. I believe him when he says he didn't cheat on me and he believes me to. I heard false positives happen. Could it be because I shaved the night before and cut myself a bit and blood got in the sample taken from me? Did they mess up the Pap smear? Is it possible they messed up in the lab? Is it possible he is immune to it or something?
(I should mention were both in the military and go to military medical facilities. Not sure if that matters or not)

[can2rene]

Here are the possibilities, assuming of course that everything you said about yourself being a virgin is true:

1) False Positive (rare)

2) False Negative (rare)

3) He had chlamydia but treated it with meds so it didn't show up on the test

4) He had chlamydia but it went away on its on after a few months

That's it. No other possibilities. Think about each of those four and ask yourself which one is most likely for your situation.

[Joy2016]

I think the lab messed up. I had a positive chlamydia test result and was completely shocked because I am in a committed relationship. I decided to take a second test. The second test was negative. Of course I cannot be sure, but it would make much more sense if the first test was wrong and the second test was the accurate one.  Both tests can't be right.  I hadn't taken any medications between the first and second tests.