Hi there,
Firstly guilt does not equal risk so relax with that.
Your tests are conclusive.
Oral sex does not transfer HIV ever and some question how easy it is to pass on chlamydia. Oral sex transmission of STIs are not common and its even less common when it comes when you are the receiver of oral sex.
Say you did have something and your own antibiotics cleared it because you had no symptoms... 1) it would depend on what antibiotics you had and also 2) the chances of both of you not having symptoms is rare.
You have nothing to worry about in relations to STIs.
Also, depending on where you are, doctors routinely test women for various things. Once I asked my doctor why she was testing me for HPV when my husband has been my only partner since we've been married (a long time). She said, "Because husbands cheat." She wasn't going to take my assurance that he wasn't cheating because too many wives naively feel this way and get caught out. I'm not saying that your wife might have been tested for chlamydia for no reason at all, but if she has had any exams related to trying to get pregnant, it's possible they ran a test for it.
That all said, if you never had chlamydia, this is a foolish worry. And the scenario in which you somehow had it but accidentally cured it by taking antibiotics seems pretty far fetched, because you need to take the right thing for the right problem. It sounds like you're acting on guilt and fumes. Try not to, you have a lot to offer.