You used a condom, so the chances of you having anything that would cause your symptoms are very, very slim.
Have you actually seen a doctor? You need to. You might have a urinary tract infection totally unrelated to this event.
Condoms break catastrophically - you wouldn't have to check it all the time and you wouldn't miss it. They don't do microscopic tears like a lot of people think. That's an old myth that won't go away.
How long had it been since you had urinated before your test?
Does your other partner give you oral sex? There are other infections that can cause urethritis from bacteria that live in the mouth - normal bacteria, things like strep throat, respiratory viruses like the cold or covid, etc.
How is your water intake? Make sure you are drinking plenty of water, and avoid alcohol and caffeine.
Go see a doctor. Ask for a urine culture and a test to look for white blood cells in your urine. They might want to do the gonorrhea and chlamydia tests again, and that's fine, but since you were recently on the doxy, you might get a false negative.