you do not get STD's like gonorrhea and NGU from protected sex-that would be on the very rare side. and never wear 2 codoms. 1 is fine, 2 can actually cause breakage.
could the discharge be urine maybe or pre seminal fluid?
it happened after I urinated or masterbated...it might be preseminal fluid, it looks like the urine and it is not colory or white
This doesn't sound like an std, but if it persists, see your doctor.