Chlamydia

So I’m 14 weeks pregnant. Got a bunch of blood work done and a pap (cause I was due), I didn’t know I was being tested for everything so I found out today I have chlamydia. Thing is I’ve only been with my partner (the father of my child) and so now he’s saying he hasn’t been with anyone. Now, I know I haven’t had anything even before him because I always got tested regularly. So I know that before meeting him I was 100% clean. So now I don’t know what to think. Is he lying? Did I get this from the toilet seat or something I’m just so confused.

Update: I confronted him about it and he said he swears to god he hasn’t been with anyone since we started dating. And then upon questioning hun further he said “ok, pretend it was me, what now?” Like what the fuck