Conflicting Chlamydia Tests

Dear Doc,
I'd been confirmed with chlamydia recently. Started showing symptoms like clockwork... 6 weeks after initial contact with a new partner. We'd been having unprotected sex multiple times over those 6 wks.

My concern now is that i found out that my partner's test came back neg. i was certain she had to have been the one that gave it to me. After all, i showed symptoms 6 weeks after we started having unprotected sex. My last sex partner before her was over a year ago and then with a long term girlfriend of 5 monogomous years. I did kissed only one other girl 3 months ago, but my symptoms were not on my mouth but on my penis via burning urination. i know symptoms could be latent for a while but it's odd that i started getting symptoms 6 wks after sleeping with this new girl.

It's baffling enough that she supposedly was not the one that gave it to me... but what's even more baffling is if I am positive, why did she not contract it from me during our frequent unprotected sex? Her test came back negative.

Is that possible??

-Very Confused