It absolutely could be a fungal infection. You took all these antibiotics needlessly, and that can kill off good bacteria that helps keep fungus in check. It also creates drug-resistant bacteria, but that's another story.
The fluconazole doesn't work for all fungal infections, so follow up with your doc. If you are still having symptoms, keep on the doc to find out what it is. Just because your std tests are negative doesn't mean you don't have something else.
However, if this is just anxiety, then address that part.
AJ
It could be a fungus, man. Talk to your doctor about it.
I'm not a doctor but I don't think you're really in trouble.
See you.